To subtract the given fractions, we need to find a common denominator. The denominators are quadratic expressions, so we will factor them first. After factoring, we will rewrite each fraction with the common denominator and then perform the subtraction.
Step 1: Factor the Denominators
We start by factoring the denominators of the fractions:
\[
x^2 - 9x + 14 = (x - 7)(x - 2)
\]
\[
x^2 - 3x + 2 = (x - 2)(x - 1)
\]
Step 2: Find the Common Denominator
The common denominator for the two fractions is:
\[
(x - 7)(x - 2)^2(x - 1)
\]
Step 3: Rewrite the Fractions
We rewrite each fraction with the common denominator:
\[
\frac{4}{(x - 7)(x - 2)} = \frac{4(x - 2)}{(x - 7)(x - 2)^2}
\]
\[
\frac{3}{(x - 2)(x - 1)} = \frac{3(x - 7)}{(x - 2)(x - 1)(x - 7)} = \frac{3(x - 7)}{(x - 7)(x - 2)(x - 1)}
\]
Step 4: Perform the Subtraction
Now we perform the subtraction:
\[
\frac{4(x - 2) - 3(x - 7)}{(x - 7)(x - 2)(x - 1)}
\]
Step 5: Simplify the Result
Simplifying the numerator:
\[
4(x - 2) - 3(x - 7) = 4x - 8 - 3x + 21 = x + 13
\]
Thus, the result is:
\[
\frac{x + 13}{(x - 7)(x - 2)(x - 1)}
\]
Final Answer
The final simplified expression is:
\[
\boxed{\frac{x + 13}{(x - 7)(x - 2)(x - 1)}}
\]