How do you get separable filter from laplacian filter?

A separable filter can be derived from a Laplacian filter by expressing the 2D filter as the outer product of two 1D filters. The Laplacian operator typically consists of a convolution kernel that highlights edges, which can be separated into two 1D kernels—one for horizontal and one for vertical direction. For example, the 2D Laplacian filter can be represented as the convolution of a vertical derivative filter (like [-1, 2, -1]) and a horizontal derivative filter, allowing for efficient computation by applying each 1D filter sequentially.