Question

If tan 40° = λ, then (tan 140° - tan 130°)/(1 + tan 140° tan 130°) = .....

(a) (1 - λ²)/λ

(b) (1 + λ²)/λ

(c) (1 + λ²)/2λ

(d) (1 - λ²)/2λ

Answer 1

(d) (1 - λ²)/2λ

Given tan 40° = λ

Now