x+3/x+2=[k/(x+2)(x-1)] +1 (x+3/x+2)-1=[k/(x+2)(x-1)] 左边通分 (x+3-x-2)/(x+2)=[k/(x+2)(x-1)] 1/(x+2)=[k/(x+2)(x-1)] 右边分母移项[1/(x+2)]*(x+2)(x-1)=k 得x-1=k 即x=k+1 方程的解为正数 即x>0 即k+1>0 所以k>-1 故k大于-1时,方程的解为正数