Differentiate using the Product Rule which states that is where and .

Differentiate using the Exponential Rule which states that is where =.

To apply the Chain Rule, set as .

The derivative of with respect to is .

Replace all occurrences of with .

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