【数学计算】1,4,5,6,4的方差是()化简求值:(xy-x²)÷x²-2xy+y²/xy×x-y/x²
1,4,5,6,4的方差是()
化简求值:(xy-x²)÷x²-2xy+y²/xy×x-y/x²
x=8y=1/3
解方程:x/x-2-1=2/4-x²