1. **State the problem:** We need to graph the function $$y = 4 \sin\left(4\left(\theta - \frac{\pi}{2}\right)\right) + 2$$ using its five critical points and characteristics.
2. **Identify key characteristics:**
- Vertical shift: 2 (the midline is $$y=2$$)
- Amplitude: 4 (the sine wave oscillates 4 units above and below the midline)
- Phase shift: $$\frac{\pi}{2}$$ to the right
- Period: $$\frac{\pi}{2}$$ (since period $$= \frac{2\pi}{b}$$ and here $$b=4$$)
- Range: from $$2 - 4 = -2$$ to $$2 + 4 = 6$$
3. **Formula for sine function with transformations:**
$$y = A \sin\left(B(\theta - C)\right) + D$$
where:
- $$A$$ is amplitude
- $$B$$ affects period $$= \frac{2\pi}{B}$$
- $$C$$ is phase shift
- $$D$$ is vertical shift (midline)
4. **Calculate critical points:**
Critical points for sine occur at multiples of quarter periods starting from phase shift:
- Period $$= \frac{\pi}{2}$$, so quarter period $$= \frac{\pi}{8}$$
- Starting at phase shift $$\frac{\pi}{2}$$, critical points are:
$$\theta = \frac{\pi}{2}, \frac{\pi}{2} + \frac{\pi}{8} = \frac{5\pi}{8}, \frac{\pi}{2} + \frac{2\pi}{8} = \frac{3\pi}{4}, \frac{\pi}{2} + \frac{3\pi}{8} = \frac{7\pi}{8}, \frac{\pi}{2} + \frac{4\pi}{8} = \pi$$
5. **Evaluate function at critical points:**
Using $$y = 4 \sin(4(\theta - \frac{\pi}{2})) + 2$$:
- At $$\theta = \frac{\pi}{2}$$:
$$y = 4 \sin(4(\frac{\pi}{2} - \frac{\pi}{2})) + 2 = 4 \sin(0) + 2 = 2$$
- At $$\theta = \frac{5\pi}{8}$$:
$$y = 4 \sin(4(\frac{5\pi}{8} - \frac{\pi}{2})) + 2 = 4 \sin(4(\frac{\pi}{8})) + 2 = 4 \sin(\frac{\pi}{2}) + 2 = 4(1) + 2 = 6$$
- At $$\theta = \frac{3\pi}{4}$$:
$$y = 4 \sin(4(\frac{3\pi}{4} - \frac{\pi}{2})) + 2 = 4 \sin(4(\frac{\pi}{4})) + 2 = 4 \sin(\pi) + 2 = 4(0) + 2 = 2$$
- At $$\theta = \frac{7\pi}{8}$$:
$$y = 4 \sin(4(\frac{7\pi}{8} - \frac{\pi}{2})) + 2 = 4 \sin(4(\frac{3\pi}{8})) + 2 = 4 \sin(\frac{3\pi}{2}) + 2 = 4(-1) + 2 = -2$$
- At $$\theta = \pi$$:
$$y = 4 \sin(4(\pi - \frac{\pi}{2})) + 2 = 4 \sin(4(\frac{\pi}{2})) + 2 = 4 \sin(2\pi) + 2 = 4(0) + 2 = 2$$
6. **Interpretation:**
- The sine wave starts at the midline value 2 at $$\theta=\frac{\pi}{2}$$.
- It reaches a maximum of 6 at $$\theta=\frac{5\pi}{8}$$.
- Returns to midline 2 at $$\theta=\frac{3\pi}{4}$$.
- Hits minimum -2 at $$\theta=\frac{7\pi}{8}$$.
- Returns to midline 2 at $$\theta=\pi$$.
7. **Summary:**
The function oscillates between -2 and 6 with period $$\frac{\pi}{2}$$, shifted right by $$\frac{\pi}{2}$$, and vertical shift 2. The critical points correspond to midline, max, midline, min, midline values respectively.
Final answer: The graph of $$y = 4 \sin\left(4\left(\theta - \frac{\pi}{2}\right)\right) + 2$$ has amplitude 4, midline $$y=2$$, period $$\frac{\pi}{2}$$, phase shift $$\frac{\pi}{2}$$ right, and critical points at $$\theta = \frac{\pi}{2}, \frac{5\pi}{8}, \frac{3\pi}{4}, \frac{7\pi}{8}, \pi$$ with corresponding $$y$$ values $$2, 6, 2, -2, 2$$ respectively.
Graph Sine D2E452
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.