∫(0,4)(∣x-1∣+∣x-3∣)dx=∫(0,1)(-x+1-x+3)dx+∫(1,3)(x-1-x+3)dx+∫(3,4)(x-1+x-3)dx
=[-x^2+4x]︱(0,1)+2*2+[x^2-4x]︱(3,4)
=-1+4+4+[(4^2-4*4]-[(3^2-4*3]=10
∫(0,4)(∣x-1∣+∣x-3∣)dx=∫(0,1)(-x+1-x+3)dx+∫(1,3)(x-1-x+3)dx+∫(3,4)(x-1+x-3)dx
=[-x^2+4x]︱(0,1)+2*2+[x^2-4x]︱(3,4)
=-1+4+4+[(4^2-4*4]-[(3^2-4*3]=10