There are 4 of them of which we may be called special products. Or in other reference there are 3.
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1.) Product involving the distributive property of multiplication
example: 3(x+y)
using distributive property you'll have:
3(x+y) = 3x + 3y
2.) Square of a Sum
example: (x+1)²
= x² + 2x + 1
3.) Square of a Difference
example: (x-1)²
= x² - 2x + 1
4.) Difference of Two Squares
example: (x+2)(x-2)
= x² - 4