2/(x+3)+2/(3－x)+(2x+18)/(x²－9）=(2x-6-2x-6+2x+18)/(x^2-9)=(2x+6)/(x^2-9)=2(x+3)/[(x+3)(x-3)]=2/(x-3)要使原式为整数，则X-3=1或X-3=2解得X=4或x=5所以符合条件的X的值有4和5，它们的和为9
