Question
Question: If \(\sin B\) =\(\frac{1}{5}\sin(2A + B)\), then \(\frac{\tan(A + B)}{\tan A} =\)...
If sinB =51sin(2A+B), then tanAtan(A+B)=
A
35
B
32
C
23
D
53
Answer
23
Explanation
Solution
sinBsin(2A+B)=15 by componendo and Dividendo.
sin(2A+B)−sinBsin(2A+B)+sinB=5−15+1
2cos(A+B).sinA2sin(A+B).cosA=46 ⇒ tanAtan(A+B)=23.