已知x的平方-4x+1=0,求x+x的-1次方-5的绝对值

来源:学生作业帮助网 编辑:作业帮 时间:2024/08/01 20:04:32
已知x的平方-4x+1=0,求x+x的-1次方-5的绝对值
xR]k@+Bal2K2?§|جdDX}VJ*/J b?'Z)Jm9{w7:8*ijl°)F v&\]T_'óoY/ɓѳrY핻'Z_||}VOz՝~Sn=6/=?~[qk+@<]~K-oJJ,Y*Y$d}x?Yrnx-B0OW֩ WWvH#F|X"fRp 1cBa%%s CHv+e!n<ƥ-_\1 u

已知x的平方-4x+1=0,求x+x的-1次方-5的绝对值
已知x的平方-4x+1=0,求x+x的-1次方-5的绝对值

已知x的平方-4x+1=0,求x+x的-1次方-5的绝对值
不清楚是求整体的绝对值,还是X与绝对值的和,下面按照求整体的绝对值解答;

x^2 - 4x + 1 = 0 ==> (x-2)^2 = 3 ==> x = 2 +- 3^(1/2)
x = 2 + 3^(1/2) ==> |x + 1/x - 5| = |2 + 3^(1/2) + 1/(2+3^(1/2)) - 5|
= 9
x = 2 - 3^(1/2) ==> |x + 1/x - 5| = |2 - 3^(1/2) + 1/(2-3^(1/2)) - 5|
= 9.
x+x的-1次方-5的绝对值=9