Trigonometryhard · Past Paper

In ABC, cot A/2 + cot B/2 + cot C/2 = ?

Acot A/2 cot B/2 cot C/2
B1
C0
Dtan A/2 tan B/2 tan C/2

✓ Correct Answer: Acot A/2 cot B/2 cot C/2

This is a conditional identity for half-angles of a triangle.

Share this question

More from Trigonometry