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प्रश्न
If f(x) = |cos x – sinx|, find `"f'"(pi/6)`
उत्तर
When 0 < x < `pi/4`,cos x > si x
So that cos x – sin x > 0
i.e. f(x) = cos x – sin x
⇒ f′(x) = – sin x – cos x
Hence `"f'"(pi/6) = - sin pi/6 - cos pi/6`
=` 1/2 (1 + sqrt(3))`.
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