求助一道题目.

/>2/(x+3)+2/(3-x)+(2x+18)/(x²-9)
=[2(x-3)-2(x+3)+(2x+18)]/(x²-9)
=(2x-6-2x-6+2x+18)/(x²-9)
=(2x+6)/(x²-9)
=2(x+3)/(x+3)(x-3)
=2/(x-3)上式为整数,则x-3能被2整除
于是x-3=±1,±2
x=4或2或5或1
符合条件x的值的和为4+2+5+1=12