Question Video: Finding the Number of Elements of a Cartesian Product of a Given Set by Itself Mathematics • Third Year of Preparatory School

Video Transcript

If 𝑋 equals zero, two, negative 13, 14, 15, find 𝑛, the number of elements in 𝑋 squared.

The set 𝑋 is made up of five values. If we were going to multiply this set by itself, 𝑋 times 𝑋, we would need to do something like this. Each term in the set must be multiplied by itself and then by the other four terms.

Let’s consider zero. It must be multiplied by itself and then by two, negative 13, 14, and 15. If we followed this procedure for each element of 𝑋, we would end up with a set of 25 elements. This question is only asking how many elements would be in this set. There would be 25.