Find an acute angle θ when cosθ-sinθcosθ+sinθ=1-31+3
(60°)
cosθ-sinθcosθ+sinθ=1-31+3
Dividing the numerator and denominator of LHS by cosθ, we get
1-tanθ1+tanθ=1-31+3
Which on simplification (or comparison) gives
tanθ=3 ⇒ θ=60°