WBJEE · Maths · Sequences and Series
If \(\left(\cot \alpha_1\right)\left(\cot \alpha_2\right) \ldots \ldots .\left(\cot \alpha_n\right)=1,0 < \alpha_1, \alpha_2, \ldots . . \alpha_n < \pi / 2\), then the maximum value of \(\left(\cos a_1\right)\left(\cos \alpha_2\right) \ldots \ldots\) \(\left(\cos \alpha_n\right)\) is given by
- A \(\frac{1}{2^{n / 2}}\)
- B \(\frac{1}{2^n}\)
- C \(\frac{1}{2 n}\)
- D 1
Answer & Solution
Correct Answer
(A) \(\frac{1}{2^{n / 2}}\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{\left(\cos \alpha_1 \cos \alpha_2 \ldots . \cos \alpha_n\right)^2}\)…
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