dx ? 0 1 x (4) (4)

ব্যাখ্যা

dx = dx = − dx 1 + x 1 + x 1 + x 1 + x 0 0 0 ∫1 1 ∫1 2 dx − dx = [2log(1 + x) − x]1 = 2log 2 − 1 1 + x 0 0 0 4 = log 4 − log e = log e