Answer :
sin 80° – cos 70° = cos 50°
⇒ sin 80° = cos 50° + cos 70°
Take RHS:
cos 50° + cos 70°
= 2 cos 60° cos (-10°)
{cos (-A) = cos A}
= cos 10°
= cos (90° - 80°)
{cos (90° - A) = sin A}
= sin 80°
= L.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:
</
