Q. 8

# Write the value o

Given to find the value for,

cos2 76o + cos2 16o – cos 76o cos 16o

In the above expression consider cos 76o cos 16o

[By using the trigonometric sum formula, we can say that,

cos(C+D) + cos ( C-D) = 2 cos C cos D]

Now multiply and divide this with 2, we get

Consider the full expression,

Multiplying and dividing the terms cos2 76° + cos2 16° with 2

[ by using the formula, cos 2θ = 2cos2θ – 1 2cos2θ = cos 2θ +1 ]

[ by using the formula, cos A + cos B ]

Hence, cos2 76o + cos2 16o – cos 76o cos 16o

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

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