Question

If sin theta =2x & xcos theta= 2, Then find value of
2(x^2+1/x^2

Answer 1

sin theta = 2x

squaring on both side

sin ^ 2 theeta = 2 { 2x^2}

2x^2 = {sin^2}/2 -------> 1

X^2 = {SIN^2}/4 --------------> 2

NOW GIVEN ::

2 { X^2 + 1 / X^2}

{2 X^2} + {2/X^2] {FROM 1 AND 2}

sin^2/2 + 2/sin^2/4

{sin ^4 + 16}/ 2sin^2