Express the product as a sum or difference. 14) sin 7x cos 4x A) (sin 11x + cos 3x) (sin 11x + sin 3x) Express the sum or difference as a product. 15) sin 75%- sin 15° A)√2 B)√2 B) sin (cos 28x2) D) (cos (cos 11x-cos3x) 04/2 D). √2 14) 15)