A Level

MATHEMATICS · Single correct · A Level · Mathematics · Trigonometry · Trigonometry

Problem

In any

\triangle ABC

\dfrac{\tan\dfrac{A}{2}-\tan\dfrac{B}{2}}{\tan\dfrac{A}{2}+\tan\dfrac{B}{2}}=

(1)

\dfrac{a-b}{a+b}

(2)

\dfrac{a-b}{c}

(3)

\dfrac{a-b}{a+b+c}

(4)

\dfrac{c}{a+b}