How do you evaluate tan(csc1(2)) without a calculator?

1 Answer
Aug 19, 2016

tan(csc1(72))=13

Explanation:

Let θ=csc1(2)

or

cscθ=2

or

1sinθ=2

or

sinθ=12

or

θ=sin1(12)

Hence

ph=12 (Since θ lies in third quadrant; hence sign not taken in consideration)

cosθ=bh

or

cosθ=h2p2h

or

cosθ=(2212)2

or

cosθ=412

or

cosθ=32

Therefore
tanθ=sinθcosθ

or

tanθ=1232

or

tanθ=13

or

tan(csc1(72))=13