已知X+y=12,xy=9,求(x²+3xy+2y²)/(x²y+2xy²) 急
问题描述:
已知X+y=12,xy=9,求(x²+3xy+2y²)/(x²y+2xy²) 急
答
x²+3xy+2y² = (X+2y)*(X+y) = (X+2y)*12x²y+2xy² = (xy)*(X+2y) = 9*(X+2y)...
已知X+y=12,xy=9,求(x²+3xy+2y²)/(x²y+2xy²) 急
x²+3xy+2y² = (X+2y)*(X+y) = (X+2y)*12x²y+2xy² = (xy)*(X+2y) = 9*(X+2y)...