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Sinmx . cosnx

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Question

sinmx . cosnx

Sum
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Solution

Let y = sinmx . cosnx

∴ `"dy"/"dx" = "d"/"dx" [(sin x)^"m" * (cos x)^"n"]`

= `(sin x)^"m"  "d"/"dx" (cos x)^"n" + (cos x)^"n"  "d"/"dx" (sin x)^"m"`

= `(sin x)^"m" "n"(cos x)^("n" - 1)  "d"/"dx" (cos x) + (cos x)^"n"  "m"(sin x)^("m" - 1)  "d"/"dx" (sin x)`

= `(sin x)^"m" "n"(cos x)^("n" - 1) (- sin x) + (cos x)^"n" "m"(sin x)^("m" - 1) cos x`

= sinm x cosn x[–n tan x + m cot 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 35 | Page 109

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