先化简,再求值,x²-1分之x-3 乘 x-3分之x²+2x+1 减 (x-1分之1 +1 ),其中x=-5分之6(要详细过程)
问题描述:
先化简,再求值,x²-1分之x-3 乘 x-3分之x²+2x+1 减 (x-1分之1 +1 ),其中x=-5分之6(要详细过程)
答
,x²-1分之x-3乘x-3分之x²+2x+1减(x-1分之1+1 )
=(x-3)/(x+1)(x-1)×(x+1)²/(x-3) -[1/(x-1)+(x-1)/(x-1)]
=(x+1)/(x-1)-x/(x-1)
=1/(x-1)
当x=-6/5时
原式=1/(-6/5-1)=-5/11