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If f(x) = |cos x|, find f'(3π4) - Mathematics

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प्रश्न

If f(x) = |cos x|, find f'`((3pi)/4)`

बेरीज
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उत्तर

When `pi/2` < x , pi, cos x < 0` 

So that |cos x| = `- cos x`

i.e., f(x) = `- cos x`

⇒ f'(x) = sin x.

Hence, `"f'"((3pi)/4) = sin ((3pi)/4) = 1/sqrt(2)`

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पाठ 5: Continuity And Differentiability - Solved Examples [पृष्ठ ९६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 5 Continuity And Differentiability
Solved Examples | Q 15 | पृष्ठ ९६

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