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`int(x(x-1))/((x^(2)+1)(x+1)sqrt(x^(3)+x^(2)+x))=(1)/(2)log|(sqrt(x+(1)/(x)+1-1))/(sqrt(x+(1)/(x)+1+1))|-A+c.` Then the value of A is equal toA. `cos^(-1)sqrt(1+(1)/(x))`B. `tan^(-1)sqrt(x+(1)/(x)+1)`C. `cot^(-1)sqrt(x+(1)/(x))`D. `sin^(-1)sqrt(x+(1)/(x)+1)` |
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Answer» Correct Answer - B We have `int(x(x-1))/((x^(2)+)(x+1)sqrt(x^(3)+x^(2)+x))dx` `=int(x(x^(2)-1))/((x^(2)+1)(x+1)^(2)sqrt(x^(3)+x^(2)+x))dx` `=int(x^(3)(1-(1)/(x^(2))))/(x^(3)(x+(1)/(x))(sqrtx+(1)/(sqrtx))^(2)sqrt(x+(1)/(x)+1))dx` `=int((1-(1)/(x^(2))))/((x+(1)/(x))(x+(1)/(x)+2)sqrt(x+(1)/(x)+1))dx` `I=int(2t)/((t^(2)-1)(t^(2)+1)sqrt(t^(2)))dt` where `x+(1)/(x)+1=t^(2)` `=int(2)/((t^(2)-1)(t^(2)+1))dt` `=int(1)/(t^(2)-1)dt-int(1)/(t^(2)+1)dt` `=(1)/(2)log|(t-1)/(t+1)|-tan^(-1)t+c` `=(1)/(2)log|(sqrt(x+(1)/(x)+1)-1)/(sqrt(x+(1)/(x)+1+1))|-tan^(-1)sqrt(x+(1)/(x)+1)+c` |
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