# Find the Derivative – d/dx y=cos(cos(x))

Differentiate using the chain rule, which states that is where and .
To apply the Chain Rule, set as .
The derivative of with respect to is .
Replace all occurrences of with .
The derivative of with respect to is .
Simplify the expression.
Multiply by .
Multiply by .
Reorder the factors of .
Find the Derivative – d/dx y=cos(cos(x))