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FOIL Calculator
Multiply binomials using the FOIL method
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📐FOIL Method
F - First
Multiply first terms of each binomial
(ax + b)(cx + d) → ax × cx
O - Outer
Multiply outer terms
(ax + b)(cx + d) → ax × d
I - Inner
Multiply inner terms
(ax + b)(cx + d) → b × cx
L - Last
Multiply last terms of each binomial
(ax + b)(cx + d) → b × d
💼Applications
Algebra
• Polynomial multiplication
• Expanding expressions
• Factoring verification
Geometry
• Area calculations
• Rectangle dimensions
• Visual proofs
Education
• Learning binomial multiplication
• Mnemonic device
• Foundation for advanced algebra
💡Common Patterns
Square of Sum
(x + a)² = x² + 2ax + a²
Square of Difference
(x - a)² = x² - 2ax + a²
Difference of Squares
(x + a)(x - a) = x² - a²
General Form
(ax + b)(cx + d) = acx² + (ad+bc)x + bd