Question

simplify: cos(6x)cos(2x)-sin(6x)sin(2x)

Answer 1

Go to your compound angle formulae; this one will stand out to you blatantly.

Answer 2

cos(6x+2x)

Answer 3

cos(8x)

Answer 4

how do you simplify this though? i am having trouble with the steps. and what is the compound formula? i don't believe we went over that in class.

Answer 5

cos(8x) is simplified.
cos(u-v)=cos(u)cos(v)+sin(u)sin(v) and
cos(u+v)=cos(u)cos(v)-sin(u)sin(v) is a couple of the formulas

Answer 6

okay, thank you so much!