/=5-/
问题描述：
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答
/=5-/2(3x+1)/(x2+3x+2)=5-2(x2+3x+2)/(3x+1)设(3x+1)/(x2+3x+2)=t则2t=5-2/t2t^2-5t+2=0(t-2)(2t-1)=0t=2或t=1/2则(3x+1)/(x2+3x+2)=22x^2+3x+1=0(x+1)(2x+1)=0x=-1或x=-1/2(3x+1)/(x2+3x+2)=1/2x^2-3x=0x(x-3)=0x=...