Question

Let f : $\R^2 → \R$ be the function defined as follows :
$f(x,y)=\begin{cases} (x^2-1)^2\cos^2(\frac{y^2}{(x^2-1)^2}) & \text{if }x \ne ±1 \\\ 0 & \text{if } x=±1\end{cases}$
The number of points of discontinuity of f(x, y) is equal to _________.

Answer 1

The correct answer is 0.