Question

先化简再求值 （x+1分之x +x^2-1分之x+1)除以(x^2+x分之x^2+1)

Answer 1

（x+1分之x +x^2-1分之x+1)除以(x^2+x分之x^2+1)

=（x/x+1 +x+1/(x+1)(x-1))/(x^2+1/x^2+x)

=（x/x+1 +1/x-1)*(x^2+x/x^2+1)

=（(x(x-1)+1)/(x+1)(x-1))*(x^2+x/(x^2+1))

=（(x^2-x+1)/(x+1)(x-1))*(x(x+1)/(x^2+1))

=x(x^2-x+1)/(x-1)(x^2+1)

=(x^3-x^2+x)/(x^3+x-x^2-1)

=(x^3-x^2+x-1+1)/(x^3-x^2+x-1)

=1+1/(x^3-x^2+x-1)

再将x的值代入,就可计算了.