Example

Simplifying (523)(5+23)(5-2\sqrt{3})(5+2\sqrt{3})

To multiply two binomials that form a conjugate pair involving radicals, such as (523)(5+23)(5 - 2\sqrt{3})(5 + 2\sqrt{3}), use the Product of Conjugates Pattern: (ab)(a+b)=a2b2(a - b)(a + b) = a^2 - b^2.

Here, a=5a = 5 and b=23b = 2\sqrt{3}. Apply the pattern: 52(23)25^2 - (2\sqrt{3})^2 Square the first term: 52=255^2 = 25. Square the second term by squaring both the numerical coefficient and the radical separately: (23)2=22(3)2=43=12(2\sqrt{3})^2 = 2^2 \cdot (\sqrt{3})^2 = 4 \cdot 3 = 12. Substitute these values back into the difference of squares: 2512=1325 - 12 = 13 The final product is the integer 1313, demonstrating that the product of conjugates containing square roots always results in an expression with no radical.

0

1

Updated 2026-05-01

Contributors are:

Who are from:

Tags

OpenStax

Intermediate Algebra @ OpenStax

Ch.8 Roots and Radicals - Intermediate Algebra @ OpenStax

Algebra

Related