2x^2-7x+2=0 求x+1/x
问题描述:
2x^2-7x+2=0 求x+1/x
答
2x^2-7x+2=0
2x-7+2/x=0
2x+2/x=7
x+1/x=7/2
希望能帮助你,如果不懂可以追问,弄懂请及时采纳。谢谢
答
2x^2-7x+2=0
2x-7+2/x =0
2/x+2/x = 7
x+1/x =7/2
答
2x^2-7x+2=0
x=[7±√(49-16)]/2*2=(7±√33)/4
1/x=(7-√33)/4 或 1/x=(7+√33)/4
x+1/x=7*2/4=7/2
答
2x^2-7x+2=0
除以2x得 x-7/2+1/x=0
x+1/x=7/2
答
等式两边同除以2x
x -(7/2) +1/x=0
x+1/x=7/2