Final answer:
The error made in subtracting the two rational expressions is that the numerator of the first expression is not being multiplied by -1. In order to subtract rational expressions, you need to have a common denominator.
Step-by-step explanation:
The error made in subtracting the two rational expressions is that the numerator of the first expression is not being multiplied by -1. In order to subtract rational expressions, you need to have a common denominator. You should multiply the numerator of the first expression by -1 before subtracting.
So the correct subtraction would be:
(1/x-2) - (1/x)
= (-1/x-2) - (1/x)
= (-1 - x-2)/(x(x-2))
= (-1 - (1/x))/((x-2)(x))
= (-1 - 1)/(x(x-2))
= -2/(x(x-2))