WBJEE · Maths · Trigonometric Ratios & Identities
The maximum and minimum values of \(\cos ^{6} \theta+\sin ^{6} \theta\) are respectively
- A 1 and \(\frac{1}{4}\)
- B 1 and 0
- C 2 and 0
- D 1 and \(\frac{1}{2}\)
Answer & Solution
Correct Answer
(A) 1 and \(\frac{1}{4}\)
Step-by-step Solution
Detailed explanation
Let \(f(\theta)=\sin ^{6} \theta+\cos ^{6} \theta\) \(\Rightarrow \quad f(\theta)=\left(\sin ^{2} \theta\right)^{3}+\left(\cos ^{2} \theta\right)^{3}\) \(=\left(\sin ^{2} \theta+\cos ^{2} \theta\right)\)…
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