\(\dfrac{4x}{(x-5)(x-3)^2} = \dfrac{A(x-3)^2+B(x-5)(x-3)+C(x-3)}{(x-5)(x-3)^2}\)
\(4x = A(x^2-6x+9) + B(x^2-8x+15)+C(x-3)\\ 4x = x^2(A + B) + x(-6A-8B+C)+(9A+15B-3C)\)
\(A+B=0\\ (-6A-8B+C)=4\\ (9A+15B-3C) = 0\)
\(\text{I leave you to solve for }A,B,C\)
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