MHT CET2018MathematicsTrigonometric Ratios & Identities
If A , B , C are the angle of Δ A B C then cot A cot B + cot B cot C + cot A cot C =
Options
- A0
- B1
- C2
- D- 1
Correct answer
B. 1
Step-by-step solution
Given A + B + C = π ⇒ A + B = π − C ⇒ cot ( A + B ) = cot ( π − C ) ⇒ cot A cot B − 1 cot A + cot B = − cot C ⇒ cot A cot B − 1 = − cot A cot C − cot B cot C ⇒ cot A cot B + cot B cot C + cot A cot C = 1