1.

If `sin(x +3alpha)=3 sin (alpha-x)`, thenA. `tan x = tan alpha`B. `tan x = tan^(2)alpha`C. `tan x = tan^(3)alpha`D. `tan x=3 tan alpha`

Answer» Correct Answer - C
`sin (x+3alpha)=3 sin (alpha - x)`
`rArr sin x cos 3alpha + sin 3 alpha cos x = 3 (sin alpha cos x - sin x cos alpha)`
`rArr sin x(cos 3alpha + 3 cos alpha) = cos x(3 sin alpha - sin 3 alpha)`
`rArr tan x = (4sin^(3)alpha)/(4 cos^(3)alpha)=tan^(3)alpha`


Discussion

No Comment Found

Related InterviewSolutions