Jawabanmu

Jawaban paling cerdas!
2014-04-19T19:28:19+07:00
Cos^4 x(1+tan^4 x)=cos^4 x(1+sin^4 x/cos^4x) = cos^4 x + sin^4 x = (cos^2 x + sin^2 x)^2 - 2sin^2 x.cos^2 x = 1 -  2sin^2 x.cos^ 2x (terbukti)
2 3 2
2014-04-19T23:46:56+07:00