Question

Write in terms of sinx and cosx only
cos2x-sinx

Answer 1

hint:
we know that cos2x=cos^2x-sin^2x

Answer 2

i.e., cos(a+b)=cosa*cosb-sina*sinb
hear a=b=x

Answer 3

okay

Answer 4

I got that identity

Answer 5

i don't understand how to plug the starting values in the equation

Answer 6

here are my answer choices.....
cos2x - sin2x - sin x

cos2x - sin3x

cos2x + sin2x + sin x

cos2x - 3 sin x
right now i have C

Answer 7

are you there?

Answer 8

your question asks to write only in cosx & sin x
but in options why you use cos2x,sin2x.....

Answer 9

you use the sum angle formulas i know that

Answer 10

i think its breaking it down

Answer 11

once again check the question and options