7、若函数f(x)
= + 2x + log2x的值域是
{3, -1,
5 + , 20},则其定义域是( B
)
A. {0,1,2,4} B. {,1,2,4} C. {,2,4} D. {,1,2,4,8}
- 答案
7、若函数f(x)
= + 2x + log2x的值域是
{3, -1,
5 + , 20},则其定义域是( B
)
A. {0,1,2,4} B. {,1,2,4} C. {,2,4} D. {,1,2,4,8}