∫(0,3)丨x^2-4丨dx
=∫(0,2)（4-x²）dx+∫(2,3)（x²-4）dx
=4x-1/3 x³|(0,2)+1/3 x³-4x|(2,3)
=8-8/3+9-12-8/3+8
=23/3