把x=2代入方程.得2×a*2-7a+3=0.即(2a-1)(a-3)=0所以a＝1/2或3设t=a*(x-1) .2×[a*(x-1) ]*2-7a*(x-1) +3=0 即 2×t*2-7t+3=0t＝1/2或3 即 a*(x-1)＝1/2或3所以当a＝1/2时.x＝2或log1/2*3当a＝1/2时.x＝2或log3*1/2...