实践与探究
例2 (x²-x+1)/(x-1),令x=2,得3
训练与提高
1、D
2、C
3、计算:
(1)4/(3a);(2)3/(10ax);(3)(-9x²)/(2y);(4)(-8x³)/(y³);
4、计算:
(1)(3y)/(16x); (2)(a+2b)/(3b);(3)(-7a²)/(6n);
(4)(-1)/(a²b²c³);(5)y³; (6)(9ab)/(2(a+b)).
拓展与延伸
5、(1)(x+y)/(xy); (2)1/(2x+y).
7、化简得x+1,取x=0,值为1.