Example

Simplifying (4+57)(457)(4+5\sqrt{7})(4-5\sqrt{7})

Evaluate the product of the conjugate pair (4+57)(457)(4 + 5\sqrt{7})(4 - 5\sqrt{7}) by applying the Product of Conjugates Pattern, (a+b)(ab)=a2b2(a + b)(a - b) = a^2 - b^2.

Identify the terms as a=4a = 4 and b=57b = 5\sqrt{7} and square them: 42(57)24^2 - (5\sqrt{7})^2 The first term squared is 1616. The second term squared is evaluated by squaring its coefficient and multiplying by the radicand: (57)2=52(7)2=257=175(5\sqrt{7})^2 = 5^2 \cdot (\sqrt{7})^2 = 25 \cdot 7 = 175. Compute the difference between these squares: 16175=15916 - 175 = -159 The final simplified result is 159-159.

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Updated 2026-05-01

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