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`int |x|ln|x|dx` equals `(x ne 0)`A. `(x^(2))/(2)ln|x|-(x^(2))/(4)+C`B. `(1)/(2)x|x|lnx+(1)/(4)x|x|+C`C. `-(x^(2))/(2)ln|x|+(x^(2))/(4)+C`D. `(1)/(2)x|x|ln|x|-(1)/(4)x|x|+C` |
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Answer» Correct Answer - D Case I If x gt 0, then `|x|=x` On applying integration by parts, we get `therefore" "=intx ln x dx=ln x.(x^(2))/(2)-int(1)/(x).(x^(2))/(2)dx` `=(x^(2))/(2).lnx-(x^(2))/(4)+C` Case II If x lt 0, then `|x|=-x` `therefore" "int |x|ln |x| dx = - int x ln (-x) dx` `-{ln(-x).(x^(2))/(2)-(x^(2))/(4)}+C` `-(x^(2))/(2)ln|x|+(x^(2))/(4)+C` Combining both cases, we get `(1)/(2)x|x|ln|x|-(1)/(4)x|x|+C` |
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