If $\sum_\limits{i=1}^n \cos ^{-1} \alpha_i=0$, then $\sum_{i=1}^n \alpha_i$

JEE MATHEMATICS MCQ: INVERSE TRIGONOMETRY

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Application +4 | -1

\sum\limits_{{i=1}}^n \cos ^{-1} \alpha_i=0

, then

\sum_{i=1}^n \alpha_i

View answer and explanation

Correct option: A

n

Option A (

n

) is correct because each

\cos^{-1} \alpha_i

must be 0, implying each

\alpha_i

is 1, and their sum is

n

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