Download the app

Questions  

 If cos1α+cos1β+cos1γ=3π , then α(β+γ)+β(γ+α)+γ(α+β) equals 

a
0
b
12
c
1
d
6

detailed solution

Correct option is D

We have, cos−1⁡α+cos−1⁡β+cos−1⁡γ=3π We know that, 0≤cos−1⁡x≤π⇒cos−1⁡α+cos−1⁡β+cos−1⁡γ=3π is possible if and only if cos−1⁡α=cos−1⁡β=cos−1⁡γ=π⇒α=β=γ=−1∴α(β+γ)+β(γ+α)+γ(α+β)=−1(−1−1)−1(−1−1)−1(−1−1)=6

Talk to our academic expert!

+91

Are you a Sri Chaitanya student?


Similar Questions

The value of tan14sin1638 is 


phone icon
whats app icon