# Find the Derivative – d/dx cos(2x)e^x

Differentiate using the Product Rule which states that is where and .
Differentiate using the Exponential Rule which states that is where =.
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 .
Differentiate.
Move to the left of .
Rewrite as .
Since is constant with respect to , the derivative of with respect to is .
Multiply by .
Differentiate using the Power Rule which states that is where .
Simplify the expression.
Multiply by .
Reorder terms.
Find the Derivative – d/dx cos(2x)e^x