math help
posted by wade .
I really don't understand how to write the expression as one invloving only sinϴ and cosϴ
sin2ϴ+cos3ϴ

math help 
Reiny
first of all you should by now have proven that
sin 2x = 2sinxcosx
by writing cos 3x as cos(2x + x), expanding that and then changing the cos 2x and sin 2x factors you can show that
cos 3x = cos^ 3x  3 sin^2 x cos x
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Please check my math answers (and correct?