Please answer the following two problems and show work Expre
Please answer the following two problems and show work.
Express the given product as a sum or difference containing only sines or cosines. sin (8x) cos (3x) sin (8x) cos (3x) Simplify your answer.)Solution
sin(8x) cos (3x)
This is of the form sin A cos B which is equal to (1/2)(sin(A+B)+sin(A-B))
so we get
(1/2)(sin(8x+3x)+sin(8x-3x))
which is equal to
(1/2)(sin (11x)+sin(5x))
sin 3x -sin x
This is of the form sin A -sin B which is equal to 2cos((A+B)/2)sin((A-B)/2
so we get
2cos((3x+x)/2)sin(3x-x)/2)
2cos 2x sin x
