Jawabanmu

2014-04-20T12:38:28+07:00
Tan x = p, maka
cos x = 1/ \sqrt{1+ p^{2} }
sin x = p /  \sqrt{1+ p^{2} }

jadi, 2 sin x. cos x = 2(1/ \sqrt{1+ p^{2} } ). (1/ \sqrt{1+ p^{2} } )
                            =  \frac{2p}{1+ p^{2} }