Questions: Consider the functions
f(x) = sin(2x)
g(x) = sin(4x).
Which statement best describes the relationship between the graphs of f(x) and g(x)?
1. The period of f is smaller than the period of g.
2. The period of f is larger than the period of g.
3. The periods of f and g are the same.
4. None of these.
Transcript text: Consider the functions
\[
\begin{array}{l}
f(x)=\sin (2 x) \\
g(x)=\sin (4 x) .
\end{array}
\]
Which statement best describes the relationship between the graphs of $f(x)$ and $g(x)$ ?
1. The period of $f$ is smaller than the period of $g$.
2. The period of $f$ is larger than the period of $g$.
3. The periods of $f$ and $g$ are the same.
4. None of these.
Solution
Solution Steps
To determine the relationship between the periods of the functions \( f(x) = \sin(2x) \) and \( g(x) = \sin(4x) \), we need to calculate the period of each function. The period of a sine function \( \sin(kx) \) is given by \( \frac{2\pi}{k} \). We will calculate the periods of \( f(x) \) and \( g(x) \) and compare them.
Solution Approach
Calculate the period of \( f(x) = \sin(2x) \).
Calculate the period of \( g(x) = \sin(4x) \).
Compare the two periods to determine the relationship.
Step 1: Calculate the Period of \( f(x) \)
The function \( f(x) = \sin(2x) \) has a period given by the formula:
\[
\text{Period of } f = \frac{2\pi}{k_f} = \frac{2\pi}{2} = \pi \approx 3.1416
\]
Step 2: Calculate the Period of \( g(x) \)
The function \( g(x) = \sin(4x) \) has a period given by the formula:
\[
\text{Period of } g = \frac{2\pi}{k_g} = \frac{2\pi}{4} = \frac{\pi}{2} \approx 1.5708
\]
Step 3: Compare the Periods
Now we compare the periods of \( f \) and \( g \):
\[
\text{Period of } f \approx 3.1416 \quad \text{and} \quad \text{Period of } g \approx 1.5708
\]
Since \( 3.1416 > 1.5708 \), we conclude that the period of \( f \) is larger than the period of \( g \).
Final Answer
The answer is that the period of \( f \) is larger than the period of \( g \). Thus, we can box the final answer as follows: