p²-q²
p²-q²= (p+q)(p-q)
[by formula: (A+B)(A-B) = A²-B²]
Proof of the formula
Proof of the formula (A+B) • (A-B)
Proof of the formula (A+B) • (A-B) = A2 - AB + BA - B2
Proof of the formula (A+B) • (A-B) = A2 - AB + BA - B2 = A2 - AB + AB - B2
Proof of the formula (A+B) • (A-B) = A2 - AB + BA - B2 = A2 - AB + AB - B2 = A2 - B2
