已知实数a满足a²+2a-8=0,求(a+1)分之1-(a²-1)分之(a+3)÷(a-1)分之(a+1)的值

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已知实数a满足a²+2a-8=0,求(a+1)分之1-(a²-1)分之(a+3)÷(a-1)分之(a+1)的值已知实数a满足a²+2a-8=0,求(a+1)分之1-(a&

已知实数a满足a²+2a-8=0,求(a+1)分之1-(a²-1)分之(a+3)÷(a-1)分之(a+1)的值
已知实数a满足a²+2a-8=0,求(a+1)分之1-(a²-1)分之(a+3)÷(a-1)分之(a+1)的值

已知实数a满足a²+2a-8=0,求(a+1)分之1-(a²-1)分之(a+3)÷(a-1)分之(a+1)的值
a²+2a-8=0
(a+4)(a-2)=0
a1=-4 a2=2
(a+1)分之1-(a²-1)分之(a+3)÷(a-1)分之(a+1)
=(a+1)分之1-(a²-1)分之(a+3)×(a+1)分之(a-1)
=(a+1)分之1-(a+1)分之(a+3)×(a+1)分之1
=(a+1)²分之(a+1)-(a+1)²分之(a+3)
=(a+1)²分之(a+1-a-3)
=-(a+1)²分之2
a=4时
原式=-25分之2
a=-2时
原式=-2

a²+2a=8
原式=1/(a+1)-(a+3)/(a+1)(a-1)×(a-1)/(a+1)
=1/(a+1)-(a+3)/(a+1)²
=(a+1-a-3)//(a+1)²
=-2/(a+1)²
=-2/(a²+2a+1)
=-2/(8+1)
=-2/9