作业帮已知a+1分之a2-9=0,试计算a2-4a+4分之a-1加上a2-4分之a2-1的值
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/10 10:39:41
已知a+1分之a2-9=0,试计算a2-4a+4分之a-1加上a2-4分之a2-1的值
已知a+1分之a2-9=0,试计算a2-4a+4分之a-1加上a2-4分之a2-1的值
已知a+1分之a2-9=0,试计算a2-4a+4分之a-1加上a2-4分之a2-1的值
a2-4a+4分之a-1加上a2-4分之a2-1
=(a-1)/(a-2)^2+(a-1)(a+1)/[(a+2)(a-2)]
=[(a-1)(a+2)+(a-1)(a+1)(a-2)/[(a+2)(a-2)^2]
=(a-1)(a+2+a^2-a-2)/[(a+2)(a-2)^2]
=a^2(a-1)/[(a+2)(a-2)^2]
a+1分之a2-9=0
(a^2-9)/(a+1)=0
a^2-9=0
a=±3
当a=3时原式=18/5
当a=-3时原式=36/25
(a^2-9)/(a+1)=0
(a+3)(a-3)/(a+1)=0
a+3=0或a-3=0
a=-3或a=3
经过检验，当a=-3、a=3时都是方程的根
a-1)/(a^2-4a+4)+(a^2-1)/(a^2-4)
=(a-1)/(a-2)^2+(a-1)(a+1/(a+2...
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(a^2-9)/(a+1)=0
(a+3)(a-3)/(a+1)=0
a+3=0或a-3=0
a=-3或a=3
经过检验，当a=-3、a=3时都是方程的根
a-1)/(a^2-4a+4)+(a^2-1)/(a^2-4)
=(a-1)/(a-2)^2+(a-1)(a+1/(a+2)(a-2)
=[(a-1)(a+2)+(a-1)(a+1)(a-2)]/(a+2)(a-2)^2
=(a-1)[(a+2)+(a+1)(a-2)]/(a+2)(a-2)
=a^2(a-1)/(a^2-4)
当a=3时，原式=9（3-1）/（9-4)=18/5
当a=-3，原式=9（-3-1）/（9-4）=-36/5
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