Question

if tan( x + y) = 3/4 and tan(x - y)= 8/15 prove that tan2x = 77/15

Answer 1

first of all
tan(x+y+x-y) = tan(x+y) + tan (x-y)/1-tan(x+y)tan(x-y)
so it be tan(2x ) = 3/4+8/15÷1 - 3/4×8/15
= 77/15

Answer 2

Answer:

right answer is 77/36 u can change your question mistake