Example

Simplifying (3−25)(3+25)(3-2\sqrt{5})(3+2\sqrt{5})

Multiply the conjugate pair (3−25)(3+25)(3 - 2\sqrt{5})(3 + 2\sqrt{5}) using the Product of Conjugates Pattern, (a−b)(a+b)=a2−b2(a - b)(a + b) = a^2 - b^2.

Set a=3a = 3 and b=25b = 2\sqrt{5} and apply the formula: 32−(25)23^2 - (2\sqrt{5})^2 Square the integer term: 32=93^2 = 9. Square the radical term by squaring the coefficient and the square root separately: (25)2=22⋅(5)2=4⋅5=20(2\sqrt{5})^2 = 2^2 \cdot (\sqrt{5})^2 = 4 \cdot 5 = 20. Calculate the difference of the two squares: 9−20=−119 - 20 = -11 The product simplifies entirely to the rational number −11-11.

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Updated 2026-06-03

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