Answer :


By regrouping the LHS and multiplying and dividing by 2 we get,



But 2cos A cos B = cos (A+B) +cos (A–B)


Then the above equation becomes,





But cos(90°–θ)=sin θ and cos(180°–θ)=–cos(θ).


Then the above equation becomes,



Now,



Substituting the corresponding values, we get







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
caricature
view all courses
RELATED QUESTIONS :

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Prove that:
</
RD Sharma - Mathematics

Mark the Correct RD Sharma - Mathematics

Mark the Correct RD Sharma - Mathematics