Mathematical formulas

Algebra

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Algebra
Powers, exponents, and radicals
Rationalization by conjugates

2. Powers, exponents, and radicals

Rationalization by conjugates

Level: fundamental

In 2. Powers, exponents, and radicals

Formula

\frac1{a+\sqrt b}=\frac{a-\sqrt b}{a^2-b}

Tags

algebra
algebra formula
powers
powers and radicals

Detail

Removes radicals from the denominator using the conjugate.

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Difference of squares
$a^2-b^2=(a-b)(a+b)$
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