College Algebra / Unit 2 Alg 070 short lesson, about 20 seconds
Squaring a Binomial
Captions available
The idea
Squaring a binomial produces a perfect square trinomial: (a + b)² = a² + 2ab + b², middle term included.
In practice
(x + 4)² runs FOIL on (x + 4)(x + 4): x² + 4x + 4x + 16 = x² + 8x + 16.
Where people slip
The middle term 2ab is the whole point.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
- Nothing. This is a starting point.
Unlocks
- Nothing yet depends on this.
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