Question

cot a - tan a =2 , find the general solutions

Answer 1

Write, cotA-tanA=2.  as:

1/tanA – tanA = 2

let tanA = t

1/t – t = 2

1 – t^2 = 2t

or

t^2 + 2t – 1 = 0

D = 4 + 4 > 0 

t = (-2 + 2root2)/2 = -1 + roott2

and = -1 – root2