Question
Question: q = tan<sup>–1</sup> (2 tan<sup>2</sup>q) – tan<sup>–1</sup> \(\left( \frac { 1 } { 3 } \tan \theta ...
q = tan–1 (2 tan2q) – tan–1 (31tanθ) then tan q =
A
–2
B
–1
C
2/3
D
2
Answer
–2
Explanation
Solution
q = tan–1 1+32tan3θ2tan2θ−31tanθ
tan q = 3+2tan3θ6tan2θ−tanθ
1 = 3+2tan3θ6tanθ−1 tan q = 0
2 tan3 q – 6 tan q + 4 = 0 ; (tan q –1)2 (tan q + 2) = 0
tan q = 1; tan q = –2; tan q = 0