1.2题计算,3题先化简,再求值,4题解方程
1(-y/3x)²×(-x/y²)³÷(y的负2方/x)
2(-5x的负2方y³)(2x的四次方y的负2方z)/10x²y
3(a/ab-b²-b/a²-ab)÷(1+a²+b²/2ab),其中a=-1+√3,b=-1-√3
4x/x-1-2/x+1=1