化简求值:【a-2/(a2+2a)-a-1/(a2+4a+4】÷a-4/a+2,其中a=-12
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/04 17:45:25
![化简求值:【a-2/(a2+2a)-a-1/(a2+4a+4】÷a-4/a+2,其中a=-12](/uploads/image/z/3722857-25-7.jpg?t=%E5%8C%96%E7%AE%80%E6%B1%82%E5%80%BC%EF%BC%9A%E3%80%90a-2%2F%EF%BC%88a2%2B2a%EF%BC%89-a-1%2F%EF%BC%88a2%2B4a%2B4%E3%80%91%C3%B7a-4%2Fa%2B2%2C%E5%85%B6%E4%B8%ADa%3D-12)
化简求值:【a-2/(a2+2a)-a-1/(a2+4a+4】÷a-4/a+2,其中a=-12
化简求值:【a-2/(a2+2a)-a-1/(a2+4a+4】÷a-4/a+2,其中a=-12
化简求值:【a-2/(a2+2a)-a-1/(a2+4a+4】÷a-4/a+2,其中a=-12
[(a-2)/(a^2+2a)-(a-1)/(a^2+4a+4)]÷(a-4)/(a+2)
=[(a-2)/a(a+2)-(a-1)/(a+2)^2]÷(a-4)/(a+2)
=[(a-2)/a(a+2)-(a-1)/(a+2)^2]*(a+2)/(a-4)
=(a-2)/a(a+2)*(a+2)/(a-4)-(a-1)/(a+2)^2*(a+2)/(a-4)
=(a-2)/a(a-4)-(a-1)/(a+2)(a-4)
=(a-2)(a+2)/a(a+2)(a-4)-a(a-1)/a(a+2)(a-4)
=[(a-2)(a+2)-a(a-1)]/a(a+2)(a-4)
=(a^2-4-a^2+a)/a(a+2)(a-4)
=(a-4)/a(a+2)(a-4)
=1/a(a+2)
=1/[-12*(-12+2)]
=1/120