Relations, mappings and function notation Quiz

1. Which relation, written as ordered pairs, is NOT a function?

• A. $(1,2),(2,3),(3,4)$
• B. $(1,5),(2,5),(3,5)$
• C. $(1,2),(1,3),(2,4)$
• D. $(0,0),(1,1),(2,4)$

2. If $f(x)=x^2+1$, find $f(3)$.

• A. $7$
• B. $10$
• C. $16$
• D. $9$

3. If $g(x)=2x-7$, solve $g(x)=9$.

• A. $x=1$
• B. $x=16$
• C. $x=11$
• D. $x=8$

4. If $f(x)=x^2-4$, find $f(-3)$.

• A. $-13$
• B. $-7$
• C. $5$
• D. $13$

5. A hire cost is $C(n)=20+4n$ for $n$ hours. What does $C(5)=40$ mean?

• A. Hiring for 5 hours costs 40
• B. Hiring for 40 hours costs 5
• C. The cost per hour is 40
• D. The fixed fee is 5