Chapter 11: Parametric Equations and Polar Coordinates - Section 11.6 - Conic Sections - Exercises 11.6 - Page 678: 13

Focus: $(0,\displaystyle \frac{1}{16})\quad$ Directrix: $y=-\displaystyle \frac{1}{16}$ .

$y=4x^{2}$ $x^{2}=\displaystyle \frac{1}{4}y,\qquad $opens up, $x^{2}=4py$ $x^{2}=4(\displaystyle \frac{1}{16})y \quad \Rightarrow \quad p=\frac{1}{16}$ Focus: $(0,\displaystyle \frac{1}{16})\quad$ Directrix: $y=-\displaystyle \frac{1}{16}$