We are given:
\[
\lim_{x \to 2} \left[ \frac{1}{x - 2} - \frac{1}{x^2 - 3x + 2} \right].
\]
Factor the denominator of the second fraction:
\[
x^2 - 3x + 2 = (x - 1)(x - 2).
\]
Thus, the expression becomes:
\[
\lim_{x \to 2} \left[ \frac{1}{x - 2} - \frac{1}{(x - 1)(x - 2)} \right].
\]
Now, find a common denominator:
\[
= \lim_{x \to 2} \frac{(x - 1) - 1}{(x - 2)(x - 1)} = \lim_{x \to 2} \frac{x - 2}{(x - 2)(x - 1)}.
\]
Canceling \( (x - 2) \) from the numerator and denominator, we get:
\[
= \lim_{x \to 2} \frac{1}{x - 1}.
\]
Substitute \( x = 2 \):
\[
= \frac{1}{2 - 1} = 1.
\]