Answer :
Take L.H.S:
cos 80° + cos 40° – cos 20°
= 2 cos 60° cos 20° – cos 20°
= cos 20° – cos 20°
= 0
= R.H.S
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
view all courses
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation


RELATED QUESTIONS :
Prove that :
<
Prove that:
</
Prove that:
</
Prove that :
<
Prove that:
</
Prove that:
</
Prove that:
</
Prove that:
</
Prove that:
</
Prove that:
</