Originally Posted by

**nee** Ok I think I got it:

sec(squared)xtanx = 2tanx

sec(squared)xtanx - 2tanx = 0

sec(squared)xtanx - tanx - tanx = 0

tanx(sec(squared)x - 2) = 0

tanx = 0 or sec(squared)x - 2 = 0

sec(squared)x = 2

secx = (squareroot)2

therefore:

a(squared) + b(squared) = c(squared)

1(squared) + b(squared) = ((squareroot)2)(squared)

1 + b(squared) = 2

1 + 1 = 2 (if I'm not mistaken)

therefore tanx = + or - 1

therefore solution set:

{0. 45, 135, 180, 225, 315)

correct me if me wrong please

NEE!!