4∫013+x2+1+x21dx−3ln3=4∫01(3+x2)−(1−x2)3+x2−1+x2dx−23ln3=2[{2x3+x2+23ln(x+3+x2)}01−{2x1+x2+21ln(x+1+x2)}01]−23ln3
=2[{214+23ln(1+4)}−{0+23ln3}−{212+21ln(1+2)}+{0+21(0)}]−23ln3
=2[1+23ln3−43ln3−21−21ln(1+2)]−23ln3=2+3ln3−23ln3−2−ln(1+2)−23ln3=2−2−ln(1+2)