∫xe^(2-x²)dx =1/2∫e^(2-x²)dx² =-1/2∫e^(2-x²)d(2-x²) =-e^(2-x²)/2+C,9,∫xe^(2-x²)dx =(-1/2)∫e^(2-x²)d(2-x²) =(-1/2)e^(2-x²) + C,0,求不定积分∫xe^(2-x²)dx
