问题
填空题
若(3x2-2x+1)(x+b)中不含x2项,则b=______.
答案
(3x2-2x+1)(x+b)=3x3+3bx2-2x2-2bx+x+b=3x3+(3b-2)x2-(2b-1)x+b,
∵结果中不含x2项,
∴3b-2=0,
解得:b=
.2 3
故答案为:
.2 3
若(3x2-2x+1)(x+b)中不含x2项,则b=______.
(3x2-2x+1)(x+b)=3x3+3bx2-2x2-2bx+x+b=3x3+(3b-2)x2-(2b-1)x+b,
∵结果中不含x2项,
∴3b-2=0,
解得:b=
.2 3
故答案为:
.2 3