Buktikan bahwa: tan [pi/4 + 1/2 arc cos (a/b)] + tan [pi/4

Buktikan bahwa: tan [pi/4 + 1/2 arc cos (a/b)] + tan [pi/4 - 1/2 arc cos (a/b)] = 2b/a (Petunjuk: misalkan arc cos (a/b) = theta berarti cos theta = a/b)