2(sin ^{6}?+cos^{6}?) - 3(sin^{4}?+cos^{4}?)+1 = 0
Ans: (Sin^{2}?)3 + (Cos^{2}?)3-3 (Sin^{4}?+(Cos^{4}?)+1=0
Consider (Sin^{2}?)3 +(Cos^{2}?)3
⇒(Sin^{2}?+Cos^{2}?)3-3 Sin^{2}?Cos^{2}?( Sin^{2}?+Cos^{2}?)
= 1- 3Sin^{2}? Cos^{2}?
Sin^{4}?+Cos^{4}?(Sin^{2}?)2+(Cos^{2}?)2
= (Sin^{2}?+Cos^{2}?)2-2 Sin^{2}? Cos^{2}?
= 1- 2 Sin^{2}? Cos^{2}?
= 2(Sin^{6}?+Cos^{6}?)-3(Sin^{4}?+Cos^{4}?) +1
= 2 (1-3 Sin^{2}? Cos^{2}?)-3 (1-2 Sin^{2}?+Cos^{2}?)+1