1. **State the problem:** We are given the exponential function $$y = \frac{1}{2} \cdot 4^x$$ and need to analyze its growth/decay, domain, range, and y-intercept.
2. **Formula and rules:** The general form of an exponential function is $$y = a \cdot b^x$$ where:
- $a$ is the initial value (y-intercept).
- $b$ is the base; if $b > 1$, the function shows exponential growth; if $0 < b < 1$, it shows exponential decay.
- The domain of any exponential function is all real numbers $\mathbb{R}$.
- The range depends on $a$ and $b$ but for $a > 0$, the range is $(0, \infty)$.
3. **Analyze the given function:**
- Here, $a = \frac{1}{2}$ and $b = 4$.
- Since $b = 4 > 1$, the function exhibits exponential growth.
- The domain is all real numbers: $$\text{Domain} = \mathbb{R}$$
- The y-intercept occurs at $x=0$:
$$y = \frac{1}{2} \cdot 4^0 = \frac{1}{2} \cdot 1 = \frac{1}{2} = 0.5$$
4. **Find the range:**
- Since $a > 0$ and $b > 1$, the function is always positive and increases without bound as $x$ increases.
- As $x \to -\infty$, $4^x \to 0$, so $y \to 0$ from above.
- As $x \to \infty$, $y \to \infty$.
- Therefore, the range is:
$$\text{Range} = (0, \infty)$$
5. **Graph shape description:**
- The graph starts near zero for large negative $x$ values.
- It passes through the y-intercept at $(0, 0.5)$.
- It increases steeply as $x$ becomes positive, showing exponential growth.
**Final summary:**
- $$y = \frac{1}{2} \cdot 4^x$$ is an exponential growth function.
- Domain: $$\mathbb{R}$$
- Range: $$(0, \infty)$$
- Y-intercept: $0.5$
Exponential Growth C6D57F
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