先化简,再计算:[(x+1/2)²+(x-1/2y)²](2x²-1/2y²),其中x=-3,y=4
问题描述:
先化简,再计算:[(x+1/2)²+(x-1/2y)²](2x²-1/2y²),其中x=-3,y=4
答
原题应为[(x+1/2y)²+(x-1/2y)²](2x²-1/2y²)=2[(x+1/y)²+(x-1/2y)²][x²-(1/2y)²]=2[(x+1/2y)²+(x-1/2y)²][x-(1/2y)][x+(1/2y)]=2[1+25](-5)(...