当a=1/3,b=-3时,求代数式a²-ab-b²/ab-b的值
问题描述：
当a=1/3,b=-3时,求代数式a²-ab-b²/ab-b的值
答
118/9
答
a,b分别代入得118/9
答
（1）a²-ab-b²/ab-b
=a²-ab-b/a-b
=(1/3)²-(1/3)(-3)-(-3)/(1/3)-(-3)
=1/9+1+9+3
=13+1/9
=118/9
（2）(a²-ab-b²)/(ab-b)
=[(1/3)²-(1/3)(-3)-(-3)²]/[(1/3)(-3)-(-3)]
=(1/9+1-9)/(-1+3)
=(1/9-8)/2
=-71/18
答
等于14 记得采纳 谢谢 祝你学习顺利
答
a²-ab-b²/ab-b
=(1/9+1-9)/(3-1)
=(-71/9)/2
=-71/18