tan-a-b-x-and-tan-a-b-y-then-tan2-

Question Number 176812 by mathlove last updated on 27/Sep/22

t a n (a - b) = x a n d t a n (a + b) = y

t h e n t a n 2 α = ?

Commented by cortano1 last updated on 27/Sep/22

\tan 2 a = ?

Answered by cortano1 last updated on 27/Sep/22

2 a = (a + b) + (a - b)

\tan 2 a = \frac{\tan (a + b) + \tan (a - b)}{1 - \tan (a + b) \tan (a - b)}

= \frac{x + y}{1 - x y}

Commented by peter frank last updated on 27/Sep/22

good

Commented by mathlove last updated on 27/Sep/22

t h a n k s