Combine the numerators over the common denominator.

Simplify the numerator.

Add and .

Subtract from .

Add and .

Cancel the common factor of and .

Factor out of .

Cancel the common factors.

Factor out of .

Cancel the common factor.

Rewrite the expression.

The left side is equal to the right side , which means that the given statement is always true.

True

Determine if True cos(pi/4)cos(pi/6)=1/2(cos(pi/12)+cos((5pi)/12))