如果(x+q)与(x+15)的积中不含x项,则q是(  ) A.15 B.5 C.-5 D.-15

问题描述:

如果(x+q)与(x+

1
5
)的积中不含x项,则q是(  )
A.
1
5

B. 5
C. -5
D. -
1
5

(x+q)(x+

1
5
)=x2+(q+
1
5
)x+
1
5
q,
因为积中不含x项,
∴q+
1
5
=0,
解得q=-
1
5

故选D.