What is the derivative of y = sinh^(-1)5x?

1 Answer
May 10, 2017

dy/dx = 5/sqrt(1 + 25x^2)

Explanation:

Let:

y = sinh^(-1)5x => sinhy=5x

Differentiating Implicitly we have:

coshy dy/dx = 5
:. dy/dx = 5/coshy

Now using the Hyperbolic Identity:

cosh^2x-sinh^2x -= 1

We can write:

cosh^2x - (5x)^2 = 1
:. cosh^2x = 1 + 25x^2
:. \ coshx = sqrt(1 + 25x^2)

So then:

dy/dx = 5/coshy

\ \ \ \ \ \ = 5/sqrt(1 + 25x^2)