Differentiability of trigonometric functions #
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Main statements #
The differentiability of the usual trigonometric functions is proved, and their derivatives are computed.
Tags #
sin, cos, tan, angle
The complex sine function is everywhere strictly differentiable, with the derivative cos x
.
The complex sine function is everywhere differentiable, with the derivative cos x
.
The complex cosine function is everywhere strictly differentiable, with the derivative
-sin x
.
The complex cosine function is everywhere differentiable, with the derivative -sin x
.
The complex hyperbolic sine function is everywhere strictly differentiable, with the derivative
cosh x
.
The complex hyperbolic sine function is everywhere differentiable, with the derivative
cosh x
.
The complex hyperbolic cosine function is everywhere strictly differentiable, with the
derivative sinh x
.
The complex hyperbolic cosine function is everywhere differentiable, with the derivative
sinh x
.
Simp lemmas for derivatives of λ x, complex.cos (f x)
etc., f : ℂ → ℂ
#
Simp lemmas for derivatives of λ x, complex.cos (f x)
etc., f : E → ℂ
#
sinh
is injective, ∀ a b, sinh a = sinh b → a = b
.