Simplify the expression algebraically

Question

Simplify the expression algebraically

4 tan( ∏/4-θ)

Answer 1

From the appropriate sum/difference identity, 4 tan(π/4 - θ) = 4 [(tan(π/4) - tan θ) / (1 + tan(π/4)•tan θ)] = 4 [(1 - tan θ) / (1 + tan θ)] because tan(π/4) = 1.