Question:

Let f(x) = \( \begin{cases} ax + 1 & \text{if } x < 1 \\ 3 & \text{if } x = 1. \text{ If } f(x) \text{ is continuous at } x = 1 \text{ then } (a - b) \text{ is equal to-} \\ bx^2 + 1 & \text{if } x > 1 \end{cases} \)