已知实数满足a^2+2a-15=0 求1/a+1 - a+2/a^2-1 / (a+1)(a+2)/a^-2a+1的值急

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已知实数满足a^2+2a-15=0 求1/a+1 - a+2/a^2-1 / (a+1)(a+2)/a^-2a+1的值急
已知实数满足a^2+2a-15=0 求1/a+1 - a+2/a^2-1 / (a+1)(a+2)/a^-2a+1的值

已知实数满足a^2+2a-15=0 求1/a+1 - a+2/a^2-1 / (a+1)(a+2)/a^-2a+1的值急
a^2+2a-15=0
a²+2a+1=16
(a+1)²=16
1/a+1 - a+2/a^2-1 / (a+1)(a+2)/a^-2a+1
=1/(a+1) -(a+2)/(a+1)(a-1) ×(a-1)²/(a+1)(a+2)
=1/(a+1)-(a-1)/(a+1)²
=(a+1-a+1)/(a+1)²
=2/(a+1)²
=2/16
=1/8