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Sinx+cos2x

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Question

`sin sqrt(x) + cos^2 sqrt(x)`

Sum
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Solution

Let y = `sin sqrt(x) + cos^2 sqrt(x)`

Differentiating both sides w.r.t. x

`"dy"/"dx" = "d"/"dx" (sin sqrt(x)) + "d"/"dx" (cos^2 sqrt(x))`

= `cos sqrt(x) * "d"/"dx" (sqrt(x)) + 2cossqrt(x)* "d"/"dx" (cos sqrt(x))`

= `cossqrt(x) * 1/(2sqrt(x)) + 2cos sqrt(x) (- sin sqrt(x)) * "d"/"dx" sqrt(x)`

= `1/(2sqrt(x)) * cos sqrt(x) - 2 cos sqrt(x) * sin sqrt(x) * 1/(2sqrt(x))`

= `(cos sqrt(x))/(2sqrt(x)) - (sin 2sqrt(x))/(2sqrt(x))`

Hence, `"dy"/"dx" = (cos sqrt(x))/(2sqrt(x)) - (sin 2sqrt(x))/(2sqrt(x))`.

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Chapter 5: Continuity And Differentiability - Exercise [Page 109]

APPEARS IN

NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 5 Continuity And Differentiability
Exercise | Q 29 | Page 109

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