statement
stringlengths
1
2.88k
proof
stringlengths
0
13.9k
type
stringclasses
10 values
symbolic_name
stringlengths
1
131
library
stringclasses
417 values
filename
stringlengths
17
80
imports
listlengths
0
16
deps
listlengths
0
64
docstring
stringlengths
0
10.2k
source_url
stringclasses
1 value
commit
stringclasses
1 value
cos_pi_div_three : cos (π / 3) = 1 / 2
begin have h₁ : (2 * cos (π / 3) - 1) ^ 2 * (2 * cos (π / 3) + 2) = 0, { have : cos (3 * (π / 3)) = cos π := by { congr' 1, ring }, linarith [cos_pi, cos_three_mul (π / 3)] }, cases mul_eq_zero.mp h₁ with h h, { linarith [pow_eq_zero h] }, { have : cos π < cos (π / 3), { refine cos_lt_cos_of_nonneg_of...
lemma
real.cos_pi_div_three
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "pow_eq_zero", "ring" ]
The cosine of `π / 3` is `1 / 2`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sq_cos_pi_div_six : cos (π / 6) ^ 2 = 3 / 4
begin have h1 : cos (π / 6) ^ 2 = 1 / 2 + 1 / 2 / 2, { convert cos_sq (π / 6), have h2 : 2 * (π / 6) = π / 3 := by cancel_denoms, rw [h2, cos_pi_div_three] }, rw ← sub_eq_zero at h1 ⊢, convert h1 using 1, ring end
lemma
real.sq_cos_pi_div_six
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "ring" ]
The square of the cosine of `π / 6` is `3 / 4` (this is sometimes more convenient than the result for cosine itself).
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_pi_div_six : cos (π / 6) = (sqrt 3) / 2
begin suffices : sqrt 3 = cos (π / 6) * 2, { field_simp [(by norm_num : 0 ≠ 2)], exact this.symm }, rw sqrt_eq_iff_sq_eq, { have h1 := (mul_right_inj' (by norm_num : (4:ℝ) ≠ 0)).mpr sq_cos_pi_div_six, rw ← sub_eq_zero at h1 ⊢, convert h1 using 1, ring }, { norm_num }, { have : 0 < cos (π / 6) :=...
lemma
real.cos_pi_div_six
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "mul_right_inj'", "ring" ]
The cosine of `π / 6` is `√3 / 2`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_pi_div_six : sin (π / 6) = 1 / 2
begin rw [← cos_pi_div_two_sub, ← cos_pi_div_three], congr, ring end
lemma
real.sin_pi_div_six
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "ring" ]
The sine of `π / 6` is `1 / 2`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sq_sin_pi_div_three : sin (π / 3) ^ 2 = 3 / 4
begin rw [← cos_pi_div_two_sub, ← sq_cos_pi_div_six], congr, ring end
lemma
real.sq_sin_pi_div_three
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "ring" ]
The square of the sine of `π / 3` is `3 / 4` (this is sometimes more convenient than the result for cosine itself).
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_pi_div_three : sin (π / 3) = (sqrt 3) / 2
begin rw [← cos_pi_div_two_sub, ← cos_pi_div_six], congr, ring end
lemma
real.sin_pi_div_three
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "ring" ]
The sine of `π / 3` is `√3 / 2`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_order_iso : Icc (-(π / 2)) (π / 2) ≃o Icc (-1:ℝ) 1
(strict_mono_on_sin.order_iso _ _).trans $ order_iso.set_congr _ _ bij_on_sin.image_eq
def
real.sin_order_iso
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "order_iso.set_congr" ]
`real.sin` as an `order_iso` between `[-(π / 2), π / 2]` and `[-1, 1]`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_sin_order_iso_apply (x : Icc (-(π / 2)) (π / 2)) : (sin_order_iso x : ℝ) = sin x
rfl
lemma
real.coe_sin_order_iso_apply
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_order_iso_apply (x : Icc (-(π / 2)) (π / 2)) : sin_order_iso x = ⟨sin x, sin_mem_Icc x⟩
rfl
lemma
real.sin_order_iso_apply
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pi_div_four : tan (π / 4) = 1
begin rw [tan_eq_sin_div_cos, cos_pi_div_four, sin_pi_div_four], have h : (sqrt 2) / 2 > 0 := by cancel_denoms, exact div_self (ne_of_gt h), end
lemma
real.tan_pi_div_four
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "div_self" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pi_div_two : tan (π / 2) = 0
by simp [tan_eq_sin_div_cos]
lemma
real.tan_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pos_of_pos_of_lt_pi_div_two {x : ℝ} (h0x : 0 < x) (hxp : x < π / 2) : 0 < tan x
by rw tan_eq_sin_div_cos; exact div_pos (sin_pos_of_pos_of_lt_pi h0x (by linarith)) (cos_pos_of_mem_Ioo ⟨by linarith, hxp⟩)
lemma
real.tan_pos_of_pos_of_lt_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "div_pos" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_nonneg_of_nonneg_of_le_pi_div_two {x : ℝ} (h0x : 0 ≤ x) (hxp : x ≤ π / 2) : 0 ≤ tan x
match lt_or_eq_of_le h0x, lt_or_eq_of_le hxp with | or.inl hx0, or.inl hxp := le_of_lt (tan_pos_of_pos_of_lt_pi_div_two hx0 hxp) | or.inl hx0, or.inr hxp := by simp [hxp, tan_eq_sin_div_cos] | or.inr hx0, _ := by simp [hx0.symm] end
lemma
real.tan_nonneg_of_nonneg_of_le_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_neg_of_neg_of_pi_div_two_lt {x : ℝ} (hx0 : x < 0) (hpx : -(π / 2) < x) : tan x < 0
neg_pos.1 (tan_neg x ▸ tan_pos_of_pos_of_lt_pi_div_two (by linarith) (by linarith [pi_pos]))
lemma
real.tan_neg_of_neg_of_pi_div_two_lt
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_nonpos_of_nonpos_of_neg_pi_div_two_le {x : ℝ} (hx0 : x ≤ 0) (hpx : -(π / 2) ≤ x) : tan x ≤ 0
neg_nonneg.1 (tan_neg x ▸ tan_nonneg_of_nonneg_of_le_pi_div_two (by linarith) (by linarith))
lemma
real.tan_nonpos_of_nonpos_of_neg_pi_div_two_le
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_lt_tan_of_nonneg_of_lt_pi_div_two {x y : ℝ} (hx₁ : 0 ≤ x) (hy₂ : y < π / 2) (hxy : x < y) : tan x < tan y
begin rw [tan_eq_sin_div_cos, tan_eq_sin_div_cos], exact div_lt_div (sin_lt_sin_of_lt_of_le_pi_div_two (by linarith) (le_of_lt hy₂) hxy) (cos_le_cos_of_nonneg_of_le_pi hx₁ (by linarith) (le_of_lt hxy)) (sin_nonneg_of_nonneg_of_le_pi (by linarith) (by linarith)) (cos_pos_of_mem_Ioo ⟨by linarith, hy₂⟩...
lemma
real.tan_lt_tan_of_nonneg_of_lt_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "div_lt_div" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_lt_tan_of_lt_of_lt_pi_div_two {x y : ℝ} (hx₁ : -(π / 2) < x) (hy₂ : y < π / 2) (hxy : x < y) : tan x < tan y
match le_total x 0, le_total y 0 with | or.inl hx0, or.inl hy0 := neg_lt_neg_iff.1 $ by rw [← tan_neg, ← tan_neg]; exact tan_lt_tan_of_nonneg_of_lt_pi_div_two (neg_nonneg.2 hy0) (neg_lt.2 hx₁) (neg_lt_neg hxy) | or.inl hx0, or.inr hy0 := (lt_or_eq_of_le hy0).elim (λ hy0, calc tan x ≤ 0 : tan_nonpos_of_nonpos_of...
lemma
real.tan_lt_tan_of_lt_of_lt_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
strict_mono_on_tan : strict_mono_on tan (Ioo (-(π / 2)) (π / 2))
λ x hx y hy, tan_lt_tan_of_lt_of_lt_pi_div_two hx.1 hy.2
lemma
real.strict_mono_on_tan
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "strict_mono_on" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
inj_on_tan : inj_on tan (Ioo (-(π / 2)) (π / 2))
strict_mono_on_tan.inj_on
lemma
real.inj_on_tan
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_inj_of_lt_of_lt_pi_div_two {x y : ℝ} (hx₁ : -(π / 2) < x) (hx₂ : x < π / 2) (hy₁ : -(π / 2) < y) (hy₂ : y < π / 2) (hxy : tan x = tan y) : x = y
inj_on_tan ⟨hx₁, hx₂⟩ ⟨hy₁, hy₂⟩ hxy
lemma
real.tan_inj_of_lt_of_lt_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_periodic : function.periodic tan π
by simpa only [function.periodic, tan_eq_sin_div_cos] using sin_antiperiodic.div cos_antiperiodic
lemma
real.tan_periodic
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "function.periodic" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_add_pi (x : ℝ) : tan (x + π) = tan x
tan_periodic x
lemma
real.tan_add_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_sub_pi (x : ℝ) : tan (x - π) = tan x
tan_periodic.sub_eq x
lemma
real.tan_sub_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pi_sub (x : ℝ) : tan (π - x) = -tan x
tan_neg x ▸ tan_periodic.sub_eq'
lemma
real.tan_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pi_div_two_sub (x : ℝ) : tan (π / 2 - x) = (tan x)⁻¹
by rw [tan_eq_sin_div_cos, tan_eq_sin_div_cos, inv_div, sin_pi_div_two_sub, cos_pi_div_two_sub]
lemma
real.tan_pi_div_two_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "inv_div" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_nat_mul_pi (n : ℕ) : tan (n * π) = 0
tan_zero ▸ tan_periodic.nat_mul_eq n
lemma
real.tan_nat_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_int_mul_pi (n : ℤ) : tan (n * π) = 0
tan_zero ▸ tan_periodic.int_mul_eq n
lemma
real.tan_int_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_add_nat_mul_pi (x : ℝ) (n : ℕ) : tan (x + n * π) = tan x
tan_periodic.nat_mul n x
lemma
real.tan_add_nat_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_add_int_mul_pi (x : ℝ) (n : ℤ) : tan (x + n * π) = tan x
tan_periodic.int_mul n x
lemma
real.tan_add_int_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_sub_nat_mul_pi (x : ℝ) (n : ℕ) : tan (x - n * π) = tan x
tan_periodic.sub_nat_mul_eq n
lemma
real.tan_sub_nat_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_sub_int_mul_pi (x : ℝ) (n : ℤ) : tan (x - n * π) = tan x
tan_periodic.sub_int_mul_eq n
lemma
real.tan_sub_int_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_nat_mul_pi_sub (x : ℝ) (n : ℕ) : tan (n * π - x) = -tan x
tan_neg x ▸ tan_periodic.nat_mul_sub_eq n
lemma
real.tan_nat_mul_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_int_mul_pi_sub (x : ℝ) (n : ℤ) : tan (n * π - x) = -tan x
tan_neg x ▸ tan_periodic.int_mul_sub_eq n
lemma
real.tan_int_mul_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_sin_pi_div_two : tendsto sin (𝓝[<] (π/2)) (𝓝 1)
by { convert continuous_sin.continuous_within_at, simp }
lemma
real.tendsto_sin_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_cos_pi_div_two : tendsto cos (𝓝[<] (π/2)) (𝓝[>] 0)
begin apply tendsto_nhds_within_of_tendsto_nhds_of_eventually_within, { convert continuous_cos.continuous_within_at, simp }, { filter_upwards [Ioo_mem_nhds_within_Iio (right_mem_Ioc.mpr (neg_lt_self pi_div_two_pos))] with x hx using cos_pos_of_mem_Ioo hx }, end
lemma
real.tendsto_cos_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "Ioo_mem_nhds_within_Iio", "tendsto_nhds_within_of_tendsto_nhds_of_eventually_within" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_tan_pi_div_two : tendsto tan (𝓝[<] (π/2)) at_top
begin convert tendsto_cos_pi_div_two.inv_tendsto_zero.at_top_mul zero_lt_one tendsto_sin_pi_div_two, simp only [pi.inv_apply, ← div_eq_inv_mul, ← tan_eq_sin_div_cos] end
lemma
real.tendsto_tan_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "div_eq_inv_mul", "pi.inv_apply", "zero_lt_one" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_sin_neg_pi_div_two : tendsto sin (𝓝[>] (-(π/2))) (𝓝 (-1))
by { convert continuous_sin.continuous_within_at, simp }
lemma
real.tendsto_sin_neg_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_cos_neg_pi_div_two : tendsto cos (𝓝[>] (-(π/2))) (𝓝[>] 0)
begin apply tendsto_nhds_within_of_tendsto_nhds_of_eventually_within, { convert continuous_cos.continuous_within_at, simp }, { filter_upwards [Ioo_mem_nhds_within_Ioi (left_mem_Ico.mpr (neg_lt_self pi_div_two_pos))] with x hx using cos_pos_of_mem_Ioo hx }, end
lemma
real.tendsto_cos_neg_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "Ioo_mem_nhds_within_Ioi", "tendsto_nhds_within_of_tendsto_nhds_of_eventually_within" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_tan_neg_pi_div_two : tendsto tan (𝓝[>] (-(π/2))) at_bot
begin convert tendsto_cos_neg_pi_div_two.inv_tendsto_zero.at_top_mul_neg (by norm_num) tendsto_sin_neg_pi_div_two, simp only [pi.inv_apply, ← div_eq_inv_mul, ← tan_eq_sin_div_cos] end
lemma
real.tendsto_tan_neg_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "div_eq_inv_mul", "pi.inv_apply" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_eq_zero_iff_cos_eq {z : ℂ} : sin z = 0 ↔ cos z = 1 ∨ cos z = -1
by rw [← mul_self_eq_one_iff, ← sin_sq_add_cos_sq, sq, sq, ← sub_eq_iff_eq_add, sub_self]; exact ⟨λ h, by rw [h, mul_zero], eq_zero_of_mul_self_eq_zero ∘ eq.symm⟩
lemma
complex.sin_eq_zero_iff_cos_eq
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "eq_zero_of_mul_self_eq_zero", "mul_self_eq_one_iff", "mul_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_pi_div_two : cos (π / 2) = 0
calc cos (π / 2) = real.cos (π / 2) : by rw [of_real_cos]; simp ... = 0 : by simp
lemma
complex.cos_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "real.cos" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_pi_div_two : sin (π / 2) = 1
calc sin (π / 2) = real.sin (π / 2) : by rw [of_real_sin]; simp ... = 1 : by simp
lemma
complex.sin_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "real.sin" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_pi : sin π = 0
by rw [← of_real_sin, real.sin_pi]; simp
lemma
complex.sin_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "real.sin_pi" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_pi : cos π = -1
by rw [← of_real_cos, real.cos_pi]; simp
lemma
complex.cos_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "real.cos_pi" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_add_pi (x : ℂ) : sin (x + π) = -sin x
sin_antiperiodic x
lemma
complex.sin_add_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_add_two_pi (x : ℂ) : sin (x + 2 * π) = sin x
sin_periodic x
lemma
complex.sin_add_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_sub_pi (x : ℂ) : sin (x - π) = -sin x
sin_antiperiodic.sub_eq x
lemma
complex.sin_sub_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_sub_two_pi (x : ℂ) : sin (x - 2 * π) = sin x
sin_periodic.sub_eq x
lemma
complex.sin_sub_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_pi_sub (x : ℂ) : sin (π - x) = sin x
neg_neg (sin x) ▸ sin_neg x ▸ sin_antiperiodic.sub_eq'
lemma
complex.sin_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_two_pi_sub (x : ℂ) : sin (2 * π - x) = -sin x
sin_neg x ▸ sin_periodic.sub_eq'
lemma
complex.sin_two_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_add_nat_mul_two_pi (x : ℂ) (n : ℕ) : sin (x + n * (2 * π)) = sin x
sin_periodic.nat_mul n x
lemma
complex.sin_add_nat_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_add_int_mul_two_pi (x : ℂ) (n : ℤ) : sin (x + n * (2 * π)) = sin x
sin_periodic.int_mul n x
lemma
complex.sin_add_int_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_sub_nat_mul_two_pi (x : ℂ) (n : ℕ) : sin (x - n * (2 * π)) = sin x
sin_periodic.sub_nat_mul_eq n
lemma
complex.sin_sub_nat_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_sub_int_mul_two_pi (x : ℂ) (n : ℤ) : sin (x - n * (2 * π)) = sin x
sin_periodic.sub_int_mul_eq n
lemma
complex.sin_sub_int_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_nat_mul_two_pi_sub (x : ℂ) (n : ℕ) : sin (n * (2 * π) - x) = -sin x
sin_neg x ▸ sin_periodic.nat_mul_sub_eq n
lemma
complex.sin_nat_mul_two_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_int_mul_two_pi_sub (x : ℂ) (n : ℤ) : sin (n * (2 * π) - x) = -sin x
sin_neg x ▸ sin_periodic.int_mul_sub_eq n
lemma
complex.sin_int_mul_two_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_add_pi (x : ℂ) : cos (x + π) = -cos x
cos_antiperiodic x
lemma
complex.cos_add_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_add_two_pi (x : ℂ) : cos (x + 2 * π) = cos x
cos_periodic x
lemma
complex.cos_add_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_sub_pi (x : ℂ) : cos (x - π) = -cos x
cos_antiperiodic.sub_eq x
lemma
complex.cos_sub_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_sub_two_pi (x : ℂ) : cos (x - 2 * π) = cos x
cos_periodic.sub_eq x
lemma
complex.cos_sub_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_pi_sub (x : ℂ) : cos (π - x) = -cos x
cos_neg x ▸ cos_antiperiodic.sub_eq'
lemma
complex.cos_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_two_pi_sub (x : ℂ) : cos (2 * π - x) = cos x
cos_neg x ▸ cos_periodic.sub_eq'
lemma
complex.cos_two_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_add_nat_mul_two_pi (x : ℂ) (n : ℕ) : cos (x + n * (2 * π)) = cos x
cos_periodic.nat_mul n x
lemma
complex.cos_add_nat_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_add_int_mul_two_pi (x : ℂ) (n : ℤ) : cos (x + n * (2 * π)) = cos x
cos_periodic.int_mul n x
lemma
complex.cos_add_int_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_sub_nat_mul_two_pi (x : ℂ) (n : ℕ) : cos (x - n * (2 * π)) = cos x
cos_periodic.sub_nat_mul_eq n
lemma
complex.cos_sub_nat_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_sub_int_mul_two_pi (x : ℂ) (n : ℤ) : cos (x - n * (2 * π)) = cos x
cos_periodic.sub_int_mul_eq n
lemma
complex.cos_sub_int_mul_two_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_nat_mul_two_pi_sub (x : ℂ) (n : ℕ) : cos (n * (2 * π) - x) = cos x
cos_neg x ▸ cos_periodic.nat_mul_sub_eq n
lemma
complex.cos_nat_mul_two_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_int_mul_two_pi_sub (x : ℂ) (n : ℤ) : cos (n * (2 * π) - x) = cos x
cos_neg x ▸ cos_periodic.int_mul_sub_eq n
lemma
complex.cos_int_mul_two_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_add_pi_div_two (x : ℂ) : sin (x + π / 2) = cos x
by simp [sin_add]
lemma
complex.sin_add_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_sub_pi_div_two (x : ℂ) : sin (x - π / 2) = -cos x
by simp [sub_eq_add_neg, sin_add]
lemma
complex.sin_sub_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_pi_div_two_sub (x : ℂ) : sin (π / 2 - x) = cos x
by simp [sub_eq_add_neg, sin_add]
lemma
complex.sin_pi_div_two_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_add_pi_div_two (x : ℂ) : cos (x + π / 2) = -sin x
by simp [cos_add]
lemma
complex.cos_add_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_sub_pi_div_two (x : ℂ) : cos (x - π / 2) = sin x
by simp [sub_eq_add_neg, cos_add]
lemma
complex.cos_sub_pi_div_two
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cos_pi_div_two_sub (x : ℂ) : cos (π / 2 - x) = sin x
by rw [← cos_neg, neg_sub, cos_sub_pi_div_two]
lemma
complex.cos_pi_div_two_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_periodic : function.periodic tan π
by simpa only [tan_eq_sin_div_cos] using sin_antiperiodic.div cos_antiperiodic
lemma
complex.tan_periodic
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "function.periodic" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_add_pi (x : ℂ) : tan (x + π) = tan x
tan_periodic x
lemma
complex.tan_add_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_sub_pi (x : ℂ) : tan (x - π) = tan x
tan_periodic.sub_eq x
lemma
complex.tan_sub_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pi_sub (x : ℂ) : tan (π - x) = -tan x
tan_neg x ▸ tan_periodic.sub_eq'
lemma
complex.tan_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_pi_div_two_sub (x : ℂ) : tan (π / 2 - x) = (tan x)⁻¹
by rw [tan_eq_sin_div_cos, tan_eq_sin_div_cos, inv_div, sin_pi_div_two_sub, cos_pi_div_two_sub]
lemma
complex.tan_pi_div_two_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "inv_div" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_add_nat_mul_pi (x : ℂ) (n : ℕ) : tan (x + n * π) = tan x
tan_periodic.nat_mul n x
lemma
complex.tan_add_nat_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_add_int_mul_pi (x : ℂ) (n : ℤ) : tan (x + n * π) = tan x
tan_periodic.int_mul n x
lemma
complex.tan_add_int_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_sub_nat_mul_pi (x : ℂ) (n : ℕ) : tan (x - n * π) = tan x
tan_periodic.sub_nat_mul_eq n
lemma
complex.tan_sub_nat_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_sub_int_mul_pi (x : ℂ) (n : ℤ) : tan (x - n * π) = tan x
tan_periodic.sub_int_mul_eq n
lemma
complex.tan_sub_int_mul_pi
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_nat_mul_pi_sub (x : ℂ) (n : ℕ) : tan (n * π - x) = -tan x
tan_neg x ▸ tan_periodic.nat_mul_sub_eq n
lemma
complex.tan_nat_mul_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tan_int_mul_pi_sub (x : ℂ) (n : ℤ) : tan (n * π - x) = -tan x
tan_neg x ▸ tan_periodic.int_mul_sub_eq n
lemma
complex.tan_int_mul_pi_sub
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_antiperiodic : function.antiperiodic exp (π * I)
by simp [exp_add, exp_mul_I]
lemma
complex.exp_antiperiodic
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "exp_add", "function.antiperiodic" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_periodic : function.periodic exp (2 * π * I)
(mul_assoc (2:ℂ) π I).symm ▸ exp_antiperiodic.periodic
lemma
complex.exp_periodic
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "function.periodic", "mul_assoc" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_mul_I_antiperiodic : function.antiperiodic (λ x, exp (x * I)) π
by simpa only [mul_inv_cancel_right₀ I_ne_zero] using exp_antiperiodic.mul_const I_ne_zero
lemma
complex.exp_mul_I_antiperiodic
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "function.antiperiodic", "mul_inv_cancel_right₀" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_mul_I_periodic : function.periodic (λ x, exp (x * I)) (2 * π)
exp_mul_I_antiperiodic.periodic
lemma
complex.exp_mul_I_periodic
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "function.periodic" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_pi_mul_I : exp (π * I) = -1
exp_zero ▸ exp_antiperiodic.eq
lemma
complex.exp_pi_mul_I
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "exp_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_two_pi_mul_I : exp (2 * π * I) = 1
exp_periodic.eq.trans exp_zero
lemma
complex.exp_two_pi_mul_I
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "exp_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_nat_mul_two_pi_mul_I (n : ℕ) : exp (n * (2 * π * I)) = 1
(exp_periodic.nat_mul_eq n).trans exp_zero
lemma
complex.exp_nat_mul_two_pi_mul_I
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "exp_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_int_mul_two_pi_mul_I (n : ℤ) : exp (n * (2 * π * I)) = 1
(exp_periodic.int_mul_eq n).trans exp_zero
lemma
complex.exp_int_mul_two_pi_mul_I
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "exp_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_add_pi_mul_I (z : ℂ) : exp (z + π * I) = -exp z
exp_antiperiodic z
lemma
complex.exp_add_pi_mul_I
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exp_sub_pi_mul_I (z : ℂ) : exp (z - π * I) = -exp z
exp_antiperiodic.sub_eq z
lemma
complex.exp_sub_pi_mul_I
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_exp_mul_exp_add_exp_neg_le_of_abs_im_le {a b : ℝ} (ha : a ≤ 0) {z : ℂ} (hz : |z.im| ≤ b) (hb : b ≤ π / 2) : abs (exp (a * (exp z + exp (-z)))) ≤ real.exp (a * real.cos b * real.exp (|z.re|))
begin simp only [abs_exp, real.exp_le_exp, of_real_mul_re, add_re, exp_re, neg_im, real.cos_neg, ← add_mul, mul_assoc, mul_comm (real.cos b), neg_re, ← real.cos_abs z.im], have : real.exp (|z.re|) ≤ real.exp z.re + real.exp (-z.re), from apply_abs_le_add_of_nonneg (λ x, (real.exp_pos x).le) z.re, refine m...
lemma
complex.abs_exp_mul_exp_add_exp_neg_le_of_abs_im_le
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/basic.lean
[ "analysis.special_functions.exp" ]
[ "exp", "mul_assoc", "mul_comm", "mul_le_mul", "mul_le_mul_of_nonpos_left", "real.cos", "real.cos_abs", "real.cos_le_cos_of_nonneg_of_le_pi", "real.cos_neg", "real.cos_nonneg_of_mem_Icc", "real.exp", "real.exp_le_exp", "real.exp_pos" ]
A supporting lemma for the **Phragmen-Lindelöf principle** in a horizontal strip. If `z : ℂ` belongs to a horizontal strip `|complex.im z| ≤ b`, `b ≤ π / 2`, and `a ≤ 0`, then $$\left|exp^{a\left(e^{z}+e^{-z}\right)}\right| \le e^{a\cos b \exp^{|re z|}}.$$
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_lt {x : ℝ} (h : 0 < x) : sin x < x
begin cases lt_or_le 1 x with h' h', { exact (sin_le_one x).trans_lt h' }, have hx : |x| = x := abs_of_nonneg h.le, have := le_of_abs_le (sin_bound $ show |x| ≤ 1, by rwa [hx]), rw [sub_le_iff_le_add', hx] at this, apply this.trans_lt, rw [sub_add, sub_lt_self_iff, sub_pos, div_eq_mul_inv (x ^ 3)], refi...
lemma
real.sin_lt
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/bounds.lean
[ "analysis.special_functions.trigonometric.arctan_deriv" ]
[ "abs_of_nonneg", "div_eq_mul_inv", "le_of_abs_le", "mul_lt_mul'", "pow_le_pow_of_le_one", "pow_pos" ]
For 0 < x, we have sin x < x.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sin_gt_sub_cube {x : ℝ} (h : 0 < x) (h' : x ≤ 1) : x - x ^ 3 / 4 < sin x
begin have hx : |x| = x := abs_of_nonneg h.le, have := neg_le_of_abs_le (sin_bound $ show |x| ≤ 1, by rwa [hx]), rw [le_sub_iff_add_le, hx] at this, refine lt_of_lt_of_le _ this, have : x ^ 3 / 4 - x ^ 3 / 6 = x ^ 3 * 12⁻¹ := by norm_num [div_eq_mul_inv, ← mul_sub], rw [add_comm, sub_add, sub_neg_eq_add, su...
lemma
real.sin_gt_sub_cube
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/bounds.lean
[ "analysis.special_functions.trigonometric.arctan_deriv" ]
[ "abs_of_nonneg", "div_eq_mul_inv", "mul_lt_mul'", "neg_le_of_abs_le", "pow_le_pow_of_le_one", "pow_pos" ]
For 0 < x ≤ 1 we have x - x ^ 3 / 4 < sin x. This is also true for x > 1, but it's nontrivial for x just above 1. This inequality is not tight; the tighter inequality is sin x > x - x ^ 3 / 6 for all x > 0, but this inequality has a simpler proof.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
deriv_tan_sub_id (x : ℝ) (h : cos x ≠ 0) : deriv (λ y : ℝ, tan y - y) x = 1 / cos x ^ 2 - 1
has_deriv_at.deriv $ by simpa using (has_deriv_at_tan h).add (has_deriv_at_id x).neg
lemma
real.deriv_tan_sub_id
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/bounds.lean
[ "analysis.special_functions.trigonometric.arctan_deriv" ]
[ "deriv", "has_deriv_at.deriv", "has_deriv_at_id" ]
The derivative of `tan x - x` is `1/(cos x)^2 - 1` away from the zeroes of cos.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
lt_tan {x : ℝ} (h1 : 0 < x) (h2 : x < π / 2) : x < tan x
begin let U := Ico 0 (π / 2), have intU : interior U = Ioo 0 (π / 2) := interior_Ico, have half_pi_pos : 0 < π / 2 := div_pos pi_pos two_pos, have cos_pos : ∀ {y : ℝ}, y ∈ U → 0 < cos y, { intros y hy, exact cos_pos_of_mem_Ioo (Ico_subset_Ioo_left (neg_lt_zero.mpr half_pi_pos) hy) }, have sin_pos : ...
theorem
real.lt_tan
analysis.special_functions.trigonometric
src/analysis/special_functions/trigonometric/bounds.lean
[ "analysis.special_functions.trigonometric.arctan_deriv" ]
[ "continuous_on", "continuous_on.mono", "continuous_on_id", "convex.strict_mono_on_of_deriv_pos", "convex_Ico", "deriv", "div_le_self", "div_pos", "gt_iff_lt", "interior", "interior_Ico", "interior_subset", "inv_one", "lt_inv", "mul_self_pos", "nat.succ_pos'", "one_div", "one_le_two...
For all `0 < x < π/2` we have `x < tan x`. This is proved by checking that the function `tan x - x` vanishes at zero and has non-negative derivative.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83