Square of a Binomial

Learn how to use binomial formulas like (a + b)², (a − b)², and (a + b)(a − b) to simplify expressions. Let’s get started! 🚀

Square of a Binomial - introduction visual

Video Lesson

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Square of a Binomial poster

Flashcards

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Expansion and simplification of (a + b)² to a² + 2ab + b² using distributive method.Square of a binomial formula, showing (a + b)² = a² + b² + 2ab with coloured squares and rectangles representing each term.Three binomial square formulas, including (a + b)² = a² + b² + 2ab, (a - b)² = a² + b² - 2ab, and (a + b)(a - b) = a² - b².Binomial expansion showing the formula (a + b)² = a² + b² + 2ab, and an example (-2x + 3)² = 4x² + 9 - 12x.Expanding the binomial (5x - 2y)² using the formula (a - b)² = a² + b² - 2ab, resulting in 25x² + 4y² - 20xy.Identifying variables a and b with signs and coefficients in the formula (a + b)(a - b) = a² - b², using (3x + 4)(3x - 4) = 9x² - 16 as an example.

🛎️ Squaring a Binomial: Where the Formula Comes From

  • Squaring a binomial means multiplying it by itself, like .
  • The middle term appears twice, which is why we get .

🛎️ Squaring a Binomial: See It Visually

  • The square splits into four parts showing , , and two rectangles.
  • Adding the areas gives .

🛎️ The 3 Key Formulas

  • .
  • .
  • .

🛎️ Using : Example

  • Identify a and b including their signs, for example in we have a = -2x and b = 3.
  • Work out squares first, then add the end term to get .

🛎️ Using : Example

  • Identify a and b including the minus sign, for example in we have a = 5x and b = 2y.
  • Work out squares first, then subtract the end term to get .

🛎️ Using : Example

  • Check the brackets use the same terms with different signs, for example .
  • Square both terms and subtract to get .

Practice Questions

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Progress1 / 6
Q1Easy

Simplify .

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