Question

If $A= (3,81)$ and $f : A \rightarrow B$ is a surjection defined by $f[x] = \log_3 x$ then $B =$

• A. [1,4]
• B. (1,4]
• C. (1,4)
• D. $[ 1, \infty)$

Answer 1

Answer: (C)

(1,4)

Answer 2

$3 < x < 81 \Rightarrow \: \log_3 3 < \log_3 x < \log_3 81$