Question

$(1+tan\alpha tan\beta )+(tan\alpha -tan\beta )$ is equal to

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

$1+ta{n}^2\alpha +ta{n}^2\beta +2tan\alpha +tan\beta +ta{n}^2\alpha +ta{n}^2\beta -2tan\alpha +tan\beta =(1+ta{n}^2\alpha )(1+ta{n}^2\beta )=se{c}^2\alpha se{c}^2\beta$