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Integrate the function in x sin 3x.

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Question

Integrate the function in x sin 3x.

Sum
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Solution

Let `I = int x. sin 3x  dx`

`= x int sin  3x  dx - int [d/dx  x int sin  3x  dx] dx`

`= x (- (cos 3x)/3) - int 1 ((- cos 3x)/3)  dx`

`= (x cos 3x)/3 + 1/3 int cos 3x  dx`

`= (x cos 3x)/3 + 1/3* (sin 3x)/3 + C`

`= - (x cos 3x)/3 + 1/9  sin 3x + C`

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Chapter 7: Integrals - Exercise 7.6 [Page 327]

APPEARS IN

NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 7 Integrals
Exercise 7.6 | Q 2 | Page 327

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