Q. 2 B3.9( 16 Votes )

# prove that :<

Answer :

LHS = sin 480° cos 690° + cos 780° sin 1050°

= sin (90° × 5 + 30°) cos (90° × 7 + 60°) + cos (90° × 8 + 60°) sin (90° × 11 + 60°)

We know that when n is odd, sin cos and cos sin.

= cos 30° sin 60° + cos 60° [-cos 60°] = 3/4 - 1/4

= 2/4

= 1/2

= RHS

Hence proved.

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 :

Prove that :
<
RD Sharma - Mathematics

prove that :
<
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Find the values oRD Sharma - Mathematics

Find the values oRD Sharma - Mathematics

Find the values oRD Sharma - Mathematics

Find the values oRD Sharma - Mathematics

prove that :
<
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Find the values oRD Sharma - Mathematics