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If `int x((ln(x+sqrt(1+x^2)))/sqrt(1+x^2)) dx=asqrt(1+x^2)ln(x+sqrt(1+x^2))+bx+c` thenA. `a=1,b=-1`B. `a=1,b=1`C. `a=-1,b=1`D. `a=-1,b=-1` |
Answer» Correct Answer - A `I=int x(In(x+sqrt(x^(2)+1)))/(sqrt(x^(2)+1))dx` `"Let " t=sqrt(x^(2)+1)` `"or " (dt)/(dx)=(x)/(sqrt(x^(2)+1))` ` :. I=int In(t+sqrt(t^(2)-1))dt ` `=In(t+sqrt(t^(2)-1))t-int(1+(t)/(sqrt(t^(2)-1)))/(t+sqrt(t^(2)-1))tdt` `=t " In"(t+sqrt(t^(2)-1))-(1)/(2)int(2t)/(sqrt(t^(2)-1))dt ` `=t" In"(t+sqrt(t^(2)-1))-sqrt(t^(2)-1)+C` `=sqrt(1+x^(2)) In (x+sqrt(1+x^(2)))-x+C` `"or " a=1,b=-1` |
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