Question

cosec²π/4-sin²π/6+2cot²π/3-sin²π/2

Answer 1

Since,
$\pi =180degree$
Then;
cos²(180/4)-sin²(180/6)+2cos²(180/3)-sin²(180/2)
=cos²45-sin²30+2cos²60-sin²90
=1/2 - 1/4 +1/2 -1
=-1/4