Question

If 2(tan^2)a * tan^2(b) * tan^2 (y) + tan^2(a)* tan^2(b) + tan^2(b) * tan^2(y) + tan^2(y)*tan^2(a) = 1
Prove that sin^2(a) + sin^2(b) + sin^2(y) = 1


******* Here a = alpha , b = beta , y = gama

Answer 1

sin^2asin^2bsin^2c + sin^2asin^2bcos^c + sin^2csin^bcos^a + sin^2csin^2acos^b +sin^2asin^2bsin^2c=cos^2acos^2bcos^2c
Try to take some terms common you will get something, then more of the manipulation. Just try it, this isn't a tough problem.

Answer 2

is it cos^c ?????????????

Answer 3

just express tan as cos/sin, then substitute cos^2 by 1-sin^2..
it is a lengthy problem, but easy..

Answer 4

sorry, sin/cos ^^

Answer 5

yes ..