已知x-1=2√2,求分式﹙x²-2x-9﹚/﹙2x²-4x-l5﹚的值
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/31 02:48:26
![已知x-1=2√2,求分式﹙x²-2x-9﹚/﹙2x²-4x-l5﹚的值](/uploads/image/z/10191080-56-0.jpg?t=%E5%B7%B2%E7%9F%A5x%EF%BC%8D1%EF%BC%9D2%E2%88%9A2%2C%E6%B1%82%E5%88%86%E5%BC%8F%EF%B9%99x%26%23178%3B%EF%BC%8D2x%EF%BC%8D9%EF%B9%9A%2F%EF%B9%992x%26%23178%3B%EF%BC%8D4x%EF%BC%8Dl5%EF%B9%9A%E7%9A%84%E5%80%BC)
x){}K+5|gѣYF:66=h{Ιjʆ@y#";g& SY-O$X;@vn~6m}Zu*
m-: Dmb$Zc~O=FjB$l@ ґ
已知x-1=2√2,求分式﹙x²-2x-9﹚/﹙2x²-4x-l5﹚的值
已知x-1=2√2,求分式﹙x²-2x-9﹚/﹙2x²-4x-l5﹚的值
已知x-1=2√2,求分式﹙x²-2x-9﹚/﹙2x²-4x-l5﹚的值
x-1=2√2
平方得 x²-2x+1=8
∴x²-2x=7
﹙x²-2x-9﹚/﹙2x²-4x-l5﹚
=(7-9)/(2×7-15)
=2