1. **State the problem:** Find the surface area of the solid formed by rotating the curve $y=2x^2$ for $0 \leq x \leq 1$ about the y-axis.
2. **Formula for surface area when rotating about the y-axis:**
$$ S = \int_a^b 2\pi x \sqrt{1 + \left(\frac{dy}{dx}\right)^2} \, dx $$
3. **Calculate the derivative:**
$$ \frac{dy}{dx} = \frac{d}{dx}(2x^2) = 4x $$
4. **Substitute into the formula:**
$$ S = \int_0^1 2\pi x \sqrt{1 + (4x)^2} \, dx = \int_0^1 2\pi x \sqrt{1 + 16x^2} \, dx $$
5. **Use substitution:** Let
$$ u = 1 + 16x^2 \implies du = 32x \, dx \implies x \, dx = \frac{du}{32} $$
6. **Rewrite the integral:**
$$ S = 2\pi \int_0^1 x \sqrt{1 + 16x^2} \, dx = 2\pi \int_{u=1}^{u=17} \sqrt{u} \frac{du}{32} = \frac{\pi}{16} \int_1^{17} u^{1/2} \, du $$
7. **Integrate:**
$$ \int u^{1/2} \, du = \frac{2}{3} u^{3/2} $$
8. **Evaluate definite integral:**
$$ S = \frac{\pi}{16} \times \frac{2}{3} \left[ u^{3/2} \right]_1^{17} = \frac{\pi}{24} (17^{3/2} - 1) $$
9. **Calculate $17^{3/2}$:**
$$ 17^{3/2} = (\sqrt{17})^3 = (4.1231)^3 \approx 70.992 $$
10. **Final surface area:**
$$ S \approx \frac{\pi}{24} (70.992 - 1) = \frac{\pi}{24} \times 69.992 \approx 9.16 $$
**Answer:** The surface area is approximately **9.16** square units.
Surface Area Y Axis 69F82B
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