已知x的平方-4x+1=0，求x-4分之2（x-1）－x分之x+6的值拜托了/(ㄒoㄒ)/~~

Question

已知x的平方-4x+1=0，求x-4分之2（x-1）－x分之x+6的值
拜托了/(ㄒoㄒ)/~~

Answer 1

x^2-4x+1=0
x^2=4x-1
2(x-1)/(x-4) - (x+6)/x
=(2x^2-2x - x^2-2x+24) /(x^2-4x)
=(x^2-4x+24)/(x^2-4x)
= 1 + 24/(x^2-4x)
=1 + 24/(-1)
=-23