expand (a+b)^2
Let's expand: (a + b)2
ⓘ Raising a sum to an integer power is multiplying it by itself: (a + b)2 = (a + b)·(a + b)
(a + b)·(a + b)
ⓘ Expand by multiplying each term inside the parentheses: (a + b)·(a + b) = a·a + ab + ba + b·b
a·a + ab + ba + b·b
ⓘ Multiplying powers with the same base adds the exponents: a·a = a2, b·b = b2■Like terms are grouped by adding their coefficients: ab + ba = 2ab
▶Expanded form:   a2 + 2ab + b2