2xy-1/2(4xy-8x²y²)+2(3xy-5x²y²),其中x=3/2,y=-2/3
问题描述:
2xy-1/2(4xy-8x²y²)+2(3xy-5x²y²),其中x=3/2,y=-2/3
答
x=3/2,y=-2/3xy=3/2*(-2/3)=-12xy-1/2(4xy-8x²y²)+2(3xy-5x²y²)=2xy-2xy+4x²y²+6xy-10x²y²=(2-2+6)xy+(4-10)x²y²=6xy-6x²y²=6xy(1-xy)=-1*[1-(-1)...