1. **State the problem:**
We need to sketch the graph of the quadratic function $$f(x) = 2x^2 - 4x - 2$$.
2. **Recall the formula for the vertex of a parabola:**
The vertex of a parabola given by $$f(x) = ax^2 + bx + c$$ is at $$x = -\frac{b}{2a}$$.
3. **Calculate the vertex:**
Given $$a=2$$, $$b=-4$$, and $$c=-2$$,
$$x = -\frac{-4}{2 \times 2} = \frac{4}{4} = 1$$.
4. **Find the y-coordinate of the vertex:**
Substitute $$x=1$$ into the function:
$$f(1) = 2(1)^2 - 4(1) - 2 = 2 - 4 - 2 = -4$$.
So, the vertex is at $$(1, -4)$$.
5. **Determine the axis of symmetry:**
The axis of symmetry is the vertical line $$x=1$$.
6. **Find the y-intercept:**
Set $$x=0$$:
$$f(0) = 2(0)^2 - 4(0) - 2 = -2$$.
So, the y-intercept is $$(0, -2)$$.
7. **Find the x-intercepts (roots):**
Solve $$2x^2 - 4x - 2 = 0$$.
Divide both sides by 2:
$$x^2 - 2x - 1 = 0$$.
Use the quadratic formula:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{2 \pm \sqrt{(-2)^2 - 4(1)(-1)}}{2} = \frac{2 \pm \sqrt{4 + 4}}{2} = \frac{2 \pm \sqrt{8}}{2} = \frac{2 \pm 2\sqrt{2}}{2} = 1 \pm \sqrt{2}$$.
So, the x-intercepts are $$1 + \sqrt{2}$$ and $$1 - \sqrt{2}$$.
8. **Sketch the graph:**
- The parabola opens upwards since $$a=2 > 0$$.
- Vertex at $$(1, -4)$$.
- Axis of symmetry at $$x=1$$.
- Y-intercept at $$(0, -2)$$.
- X-intercepts at approximately $$(1 + 1.414, 0) = (2.414, 0)$$ and $$(1 - 1.414, 0) = (-0.414, 0)$$.
This information allows plotting the parabola accurately on the grid from -6 to 6 on both axes.
**Final answer:** The graph is a parabola opening upwards with vertex at $$(1, -4)$$, axis of symmetry $$x=1$$, y-intercept at $$(0, -2)$$, and x-intercepts at $$1 \pm \sqrt{2}$$.
Parabola Graph
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