If the tangents on the ellipse $4x^2 + y^2 = 8$ at the points $(1,2)$ and $(a,b)$ are perpendicular to each other, then $a^2$ is equal to (1) $\frac{2}{17}$ (2) $\frac{4}{17}$ (3) $\frac{64}{17}$ (4) $\frac{128}{17}$
If the tangents on the ellipse $4x^2 + y^2 = 8$ at the points $(1,2)$ and $(a,b)$ are perpendicular to each other, then $a^2$ is equal to\\
(1) $\frac{2}{17}$\\
(2) $\frac{4}{17}$\\
(3) $\frac{64}{17}$\\
(4) $\frac{128}{17}$