If $\sum_\limits {i=1}^{10} \cos ^{-1} x_i=0$, then $\sum_\limits {i=1}^{10} x_i$ is

JEE MATHEMATICS MCQ: INVERSE TRIGONOMETRY

1 Hard

1 of 1

Application +4 | -1

\sum\limits_{{i=1}}^{10} \cos ^{-1} x_i=0

, then

\sum\limits_{{i=1}}^{10} x_i

View answer and explanation

Correct option: B

Option B (10) is correct because each term in the summation must be zero, implying each

x_i

is 1, and the sum of ten 1's is 10.

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