What is the derivative of $cos(tan x)$ ?

Question

1510 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-04-29T23:33:21

I would use the Chain Rule deriving $cos$ first as it is and then the argument:
$y'=-sin(tan(x))*1/cos^2(x)$

What is the derivative of cos(tan x)cos(tan x)?