Question

Rewrite with only sin x and cos x.
sin 3x

Answer 1

Is this the correct answer?

2 cos^2x sin x + sin x - 2 sin^3x

Answer 2

use sin(a+b)
write sin(2x+x)
then use formula

Answer 3

which gives you sin2xcosx+cos2xsinx :)

Answer 4

finally
sin3x=3sinx-4(sinx)^3

Answer 5

now you can wtire sin2x = sin(x+x)
and cos2x= cos(x+x)
apply the formula for them
you will get all terms in form of sin x and cos x :D

Answer 6

2 cos^2x sin x + sin x - 2 sin^3x
is also correct.
but that can be simplified using
cos^2 x = 1-sin^2 x
and then your answer will only be in sin x

Answer 7

Thanks for your help guys!

Answer 8

^^ welcome