Question

sin^4B+ 2sin^2B( 1-1/cosec^2B) +cos^4B=1

prove it

Answer 1

HELLP FRIEND,

HERE IS YOUR SOLUTION,

firstly, solve bracket to make que. easy

1-1/cosec^2B =》 1-sin^2B=》cos^2B

NOW, It is seem like,

sin^4B + 2sin^2B × cos^2B + cos^4B

now, it is also seem like a formula of (a+b)^2

then, ( sin^2B + cos^2B )

which is equal to 1

HENCE PROVED