(1)3(x+2)的平方=x的平方-4 3(x+2)^2=(x+2)(x-2)3(x+2)^2-(x+2)(x-2)=0(x+2)(3x+6-x+2)=0,(x+2)(2x+8)=0,2(x+2)(x+4)=0x+2=0,x+4=0,x1=-2.x=-4, (2)t的平方-6t-9991=0(t-103)(t+97)=0t-103=0,t+97=0,t1=103,t2=-97
(3)2(3x-1)的平方=2分之9(3x-1)^2=9/43x-1=3/2,3x-1=-3/2x1=5/6,x2=-1/6... |