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

= 1-(x- 1)

=2-x

=2-(- 1/3)

=7/3。

48。 After naming the original fractional equation, sort it out:

(m- 1)x+2=0

Because when x= plus or minus 2, the denominator of the original fractional equation is 0, which will produce root increase.

So plus or minus 2(m- 1)+2=0.

M=0 or m=2.

49。 After removing the naming and brackets from the original fractional equation, we get:

x^2+(k-2)x-4=0

Because the original fractional equation has increasing roots,

So the common denominator 3x(x- 1)=0.

x 1=0，x2= 1，

When x=0,0+0-4 = 0, the equation does not hold, so x = 0 is not an incremental root.

When x= 1, 1+k-2-4=0, k=5,

So the root of the original fractional equation is x = 1, and the value of k is k=5.

50。 Rooting may be: x=3, or x=-4.