x的平方-X-1=0,求X的4次方+2X+1除以X的5次方

网友回答

由x^2-x-1=0,得x^2=x=1;
所以(x^4+2x+1)/x^5
=(x^4+x+x+1)/x^5
=(x^4+x+x^2)/x^5
=x(x^3+x+1)/x^5
=x(x^3+x^2)/x^5
=(x^3)(x+1)/x^5
=(x^3)(x^2)/x^5
=x^5/x^5
=1