Question

Prove that

(Sin^4a + cos^4a)/ 1-2sin^2a cos^2a = 1

Answer 1

2/3= sin^4 A - cos^4 A. =(sin^2 A+ cos^2 A)( sin^2 A - cos^2 A). =1(sin^2 A- cos^2 A). ( since sin^2 A+cos^2 A =1). ={sin^2 A-(1-sin^2 A)}.

Answer 2

equate right and left side