prove that sinx=sin2x/2cosx?

2007-05-23 12:45:42 · 2 answers · asked by jermaine d 1 in Science & Mathematics ➔ Mathematics

A one-line proof:

sin (2x)/(2 cos x) = (2 sin x cos x)/(2 cos x) = sin x. Q.E.D.

2007-05-23 12:50:07 · answer #1 · answered by Pascal 7 · 0⤊ 0⤋

RHS = sin2x/2cosx
= 2sinxcosx/2cosx (explanding for sin2x)
= sinx = LHS (2cosx cancels out)

2007-05-23 19:51:14 · answer #2 · answered by beni269 2 · 0⤊ 0⤋

fedest.com, questions and answers