請教差動放大電路的靜態工作點的計算.

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如圖所示差放,T1,T2,T3的β=80,VBE=0.7V.求ICQ1?
求解過程如下:
1>.IE3=[Rb2Vee/(Rb1+Rb2)-VBE]/Re3=(3.337-0.7)/27=0.0978mA;
2>.IC3=[β/(1+β)]IE3=0.0965mA
2>.IEQ1=IC3/2=0.0489mA;
3>.ICQ1=[β/(1+β)]*IEQ1=0.047mA;

而書上給出的答案是:ICQ1=0.152mA
不知是哪部份計算有誤,請幫忙指正.謝謝!