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Question
Choose the correct alternative:
Let fk(x) = `1/"k" [sin^"k" x + cos^"k" x]` where x ∈ R and k ≥ 1. Then f4(x) − f6(x) =
Options
`1/4`
`1/12`
`1/6`
`1/3`
Solution
`1/12`
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