Solution: (first connect the denominator to the right) A(x-2)+B(x- 1) (then go to the denominator and look at the numerator directly)

Left = - 3x-4 = a (x-2)+b (x- 1)

(x- 1)(x-2) (simplified evaluation) 3x-4=Ax+Bx-2A-B

3x-4=(A+B)x-(2A+B)

{A+B=3

2A+B=4

A= 1 B=2

Answer finished ~~O(∩_∩)O~