Calc help? I have the test in 10 minutes!?

0 ⤊

why does:

sin4x=2sin2xcos2x
-2integral2 sin2xcos2xdx
etc..

where did the -2 out in front come from?!

2007-02-12 03:31:45 · 2 answers · asked by Anna 2 in Science & Mathematics ➔ Mathematics

im trying to find where the negative 2 comes from out in front of the integral.

2007-02-12 09:12:13 · update #1

sin4x = sin(2x+2x) = sin2xcos2x + sin2xcos2x = 2sin2xcos2x

2007-02-12 05:25:11 · answer #1 · answered by bozo 4 · 0⤊ 0⤋

maybe from sin 4x = sin (2x + 2x)?

2007-02-12 11:35:24 · answer #2 · answered by bequalming 5 · 0⤊ 1⤋