1) The integral ∫(1+x−1x)ex+1xdx id equal to A) (x−1)ex+1/x+C B) xex+1/x+C C) (x+1)ex+1/x+C D) −xex+1/x+C Answer: Option BExplanation:∫(1+x−1x)ex+1xdx = ∫ex+1xdx+∫x(1−1x2)ex+1xdx = ∫ex+1/xdx+xex+1/x−∫ddx(x)ex+1/xdx = ∫ex+1/xdx+xex+1/x−∫ex+1xdx [∵∫(1−1x2)ex+1/xdx=ex+1/x] =∫ex+1/xdx+xex+1/x−∫ex+1/xdx = xex+1/x+C