2.5 Composite and inverse functions Quiz

1. $f(x) = 2x + 1$ and $g(x) = x^2$. Find $(g \circ f)(-2)$.

• A. $9$
• B. $-3$
• C. $8$
• D. $4$

2. $f(x) = x - 3$ and $g(x) = 4x$. Which is $(f \circ g)(x)$?

• A. $4x - 12$
• B. $4x - 3$
• C. $4x^2 - 12x$
• D. $x + 1$

3. $f(x) = \frac{x + 7}{2}$. Find $f^{-1}(x)$.

• A. $\frac{2}{x + 7}$
• B. $2x + 7$
• C. $2x - 7$
• D. $\frac{x - 7}{2}$

4. If $f^{-1}(x) = 3x - 5$, what is $(f \circ f^{-1})(10)$?

• A. $25$
• B. $10$
• C. $5$
• D. $\frac{1}{10}$

5. Which function is its own inverse?

• A. $f(x) = x + 1$
• B. $f(x) = 2x$
• C. $f(x) = 6 - x$
• D. $f(x) = x^2$, $x \ge 0$