Q. 7 E4.5( 2 Votes )

# Solve the followi

Ideas required to solve the problem:

The general solution of any trigonometric equation is given as –

• sin x = sin y, implies x = nπ + (– 1)ny, where n Z.

• cos x = cos y, implies x = 2nπ ± y, where n Z.

• tan x = tan y, implies x = nπ + y, where n Z.

given,

sin x – 3 sin 2x + sin 3x = cos x – 3 cos 2x + cos 3x

(sin x + sin 3x) – 3sin 2x – (cos x + cos 3x) + 3 cox 2x = 0

sin A + sin B =

2 sin 2x cos x – 3 sin 2x – 2 cos 2x cos x + 3 cos 2x = 0

sin 2x ( 2cos x – 3) - cos 2x (2cos x – 3) = 0

(2cos x – 3)(sin 2x – cos 2x) = 0

cos x = 3/2 = 1.5 (not accepted as cos x lies between – 1 and 1)

Or sin 2x = cos 2x

tan 2x = 1 = tan π/4

If tan x = tan y, implies x = nπ + y, where n Z.

2x = nπ + π/4

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses
RELATED QUESTIONS :

Solve the followiRD Sharma - Mathematics

3sin2 RD Sharma - Mathematics

Solve the followiRD Sharma - Mathematics

Solve : <span lanRD Sharma - Mathematics

Solve the followiRD Sharma - Mathematics

Solve : <span lanRD Sharma - Mathematics

Solve the followiRD Sharma - Mathematics

Solve the followiRD Sharma - Mathematics

Find the general RD Sharma - Mathematics

Find the general RS Aggarwal - Mathematics