Question

If tan^2x = 4 - 2tanx, then tanx = _____.


-1 ± sqroot 5
-1 ± sq.root 3
1 ± sq.root 3
1 ± sq.root 5

Answer 1

if you look closely this represents a quadratic equation, maybe that will help you

Answer 2

Make the substitution, tan(x) = t
You will get a quadratic equation in t.
solve for t
then put back tan(x) in the place of t.

Answer 3

If you look at
x^2=2x+4

you would notice that is a quadratic because it has terms of x^2, terms of x and a constant.
Same applies when you have tanx instead of x