x^2+1/x^2=(x+1/x)^2-23x-1+1/(3x-1)=(x+1/x)^2-23x+1/(3x-1)=(x+1/x)^2-1x^2+1+1/x^2=(x+1/x)^2-1x^2+1/x^2=(x+1/x)^2-2………………后来的我也忘记了
x^2 - 3x + 1 = 0x1 = (3 + √5)/2x2 = (3 - √5)/21/x1 = 2/(3 + √5) = (3 - √5)/2 = 1/x2所以，只要使用一个根即可求出两个式子：x1 + x2 = 3x1*x2 = 1x^2 + 1/x^2= x1^2 + x2^2= (x1 + x2)^2 - 2*x1*x2= 9 - 2= 7x^4 + 1/x^4= x1^4 + x2^4= (x1^2 + x2^2)^2 - 2*(x1*x2)^2= 7^2 - 2= 47
因为X^2-3X+1=0所以X-3+1/X＝0X+1/X＝3（X+1/X）^2＝9X^2+2+1/X^2＝9X^2+1/X^2＝7因为X^2+1/X^2＝7所以（X^2+1/X^2）^2＝49X^4+2+1/X^4＝49X^4+1/X^4＝47
因为x^2-3*x+1=0所以x+1/x=3(x不等于0，两边同除x)∴x^2+1/x^2=(x+1/x)^2-2=7∴x^4+1/x^4=(x^2+1/x^2)^2-2=47
答：已知X平方-3X+1=0，试求下列各式的值：初一解法谢谢大家 （1）X平方+X平方之1； 已知x^2-3x+1=0，很显然x≠0 所以，等式两边同除以x得到：x...详情>>
