Question

Buktikan soal no. 5 dengan sifat sin^2teta + cos^2teta = 1

Answer 1

Buktikan
sin^6 A + cos^6 A = 1 - 3 sin^2 A cos^2 A
sin^6 A + cos^6 A = (sin^2 A + cos^2 A)^3 - 3 sin^2 cos^2 (sin^2 + cos^2)
sin^6 A + cos^6 A = 1 - 3 sin^2 cos^2
terbukti :)