已知m²-5m-1=0,则2m²-5m+﹙m²﹚分之1=
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/24 10:26:14
![已知m²-5m-1=0,则2m²-5m+﹙m²﹚分之1=](/uploads/image/z/5363445-21-5.jpg?t=%E5%B7%B2%E7%9F%A5m%26%23178%3B-5m-1%3D0%2C%E5%88%992m%26%23178%3B-5m%EF%BC%8B%EF%B9%99m%26%23178%3B%EF%B9%9A%E5%88%86%E4%B9%8B1%3D)
已知m²-5m-1=0,则2m²-5m+﹙m²﹚分之1=
已知m²-5m-1=0,则2m²-5m+﹙m²﹚分之1=
已知m²-5m-1=0,则2m²-5m+﹙m²﹚分之1=
m²-5m-1=0
同除以m
m-1/m=5
平方
m²+1/m²-2=25
所以 m²+1/m²=27
所以 2m²-5m+﹙m²﹚分之1=(m²-5m)+(m²+1/m²)=1+27=28