Question

已知x^2_5x_2009=0,则代数式(x_2)^2_(x_1)^2+1/x_2的值为（ ）若分式3/x_1的值是正整

Answer 1

1.已知x^2-5x-2009=0,则x^=5x+2009,代数式

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

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

=(-2x^+7x-5)/(x-2)

=(-10x-4018+7x-5)/(x-2)

=(-3x-4023)/(x-2)

=-3-4029/(x-2),

它的值为（繁 ）.

请检查题目.

2.若分式3/（x-1）的值是正整数,则x-1=1或3,整数x的值是2或4.