1. **Stating the problem:**
We are given the quadratic function $f(x) = 2(x+1)^2 + 1$ and asked to find the vertex coordinates.
2. **Formula and rules:**
The vertex form of a quadratic function is $f(x) = a(x-h)^2 + k$, where $(h,k)$ is the vertex.
3. **Identify vertex:**
Here, $a=2$, $h=-1$, and $k=1$ directly from the formula.
4. **Answer:**
The vertex of the parabola is at the point $\boxed{(-1, 1)}$.
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1. **Stating the problem:**
Convert $f(x) = 2(x+1)^2 + 1$ to the general form $ax^2 + bx + c$.
2. **Formula:**
Expand the square: $(x+1)^2 = x^2 + 2x + 1$.
3. **Intermediate work:**
$$f(x) = 2(x^2 + 2x + 1) + 1 = 2x^2 + 4x + 2 + 1 = 2x^2 + 4x + 3$$
4. **Answer:**
The general form is $\boxed{2x^2 + 4x + 3}$.
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1. **Stating the problem:**
Find the intersection of $f(x) = 2x^2 + 4x + 3$ with the $y$-axis.
2. **Rule:**
The $y$-axis corresponds to $x=0$.
3. **Calculation:**
$$f(0) = 2(0)^2 + 4(0) + 3 = 3$$
4. **Answer:**
The graph intersects the $y$-axis at $\boxed{(0, 3)}$.
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1. **Stating the problem:**
Find intervals where $f(x) = 2(x+1)^2 + 1$ is increasing or decreasing.
2. **Rule:**
Since $a=2 > 0$, parabola opens upwards.
Vertex at $x=-1$ is minimum point.
3. **Intervals:**
- Decreasing on $(-\infty, -1)$
- Increasing on $(-1, +\infty)$
4. **Answer:**
$f$ is decreasing on $(-\infty, -1)$ and increasing on $(-1, +\infty)$.
---
"slug":"quadratic vertex",
"subject":"algebra",
"svg":"",
"desmos":{"latex":"y=2(x+1)^2+1","features":{"intercepts":true,"extrema":true}},
"q_count":1
Quadratic Vertex F56658
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