∫(x²-2x+1/2)dx
=1/3·x³-x²+x/2+C是整个x平方-2x+2柿子分之1∫1/(x²-2x+2) dx=∫1/[(x-1)²+1] dx=∫1/[(x-1)²+1] d(x-1)=arctan(x-1)+C