Question

先化简在求值：a＋2分之a－1乘a 的平方－2a＋1分之a 方－4除a 方－1分之1,其中a 满足a 方－a 等于201

Answer 1

(a-1)/(a+2)*(a^2-4)/(a^2-2a+1)÷1/(a^2-1)

=(a-1)/(a+2)*(a+2)(a-2)/(a-1)^2*(a+1)(a-1)

=(a+1)(a-2)

=a^2-a-2

=2010-2

=2008