\[\boxed{\mathbf{74.}}\]
\[\textbf{а)}\ y = ax^{2} - парабола;\ \ (1;2):\]
\[2 = a \cdot 1^{2}\]
\[a = 2.\]
\[Ответ:парабола\ y = 2x^{2}.\]
\[\textbf{б)}\ y = ax^{2} - парабола;\ \ (1; - 2):\]
\[- 2 = a \cdot 1^{2}\]
\[a = - 2.\]
\[Ответ:парабола\ y = - 2x^{2}.\]
\[\textbf{в)}\ x = ay^{2} - парабола;(2;1):\]
\[2 = a \cdot 1^{2}\]
\[a = 2.\]
\[Ответ:парабола\ x = 2y^{2}.\]
\[\textbf{г)}\ x = ay^{2} - парабола;\ \ ( - 2;1):\]
\[- 2 = a \cdot 1^{2}\]
\[a = - 2.\]
\[Ответ:парабола\ x = - 2y^{2}.\]
\[\textbf{д)}\ y = a(x - 1)^{2} +\]
\[+ 1 - парабола;\ \ (0;3):\]
\[3 = a \cdot (0 - 1)^{2} + 1\]
\[a = 2.\]
\[Ответ:парабола\ y =\]
\[= 2 \cdot (x - 1)^{2} + 1.\]
\[\textbf{е)}\ y = a(x - 1)^{2} +\]
\[+ 2 - парабола;(0;0):\]
\[0 = a(0 - 1)^{2} + 2\]
\[a = - 2.\]
\[Ответ:парабола\ \]
\[y = - 2 \cdot (x - 1)^{2} + 2.\]