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Multiple Choice
Rationalize the denominator and simplify the radical expression. 2+32−3
A
7−43
B
7+431
C
7+43
D
7−431
Verified step by step guidance
1
Identify the expression to be rationalized: \( \frac{2 - \sqrt{3}}{2 + \sqrt{3}} \).
To rationalize the denominator, multiply both the numerator and the denominator by the conjugate of the denominator. The conjugate of \( 2 + \sqrt{3} \) is \( 2 - \sqrt{3} \).
Simplify the denominator using the difference of squares formula: \((a + b)(a - b) = a^2 - b^2\). Here, \(a = 2\) and \(b = \sqrt{3}\), so the denominator becomes \(2^2 - (\sqrt{3})^2 = 4 - 3 = 1\).
Simplify the numerator by expanding \((2 - \sqrt{3})^2\) using the formula \((a - b)^2 = a^2 - 2ab + b^2\). Here, \(a = 2\) and \(b = \sqrt{3}\), so the numerator becomes \(4 - 4\sqrt{3} + 3 = 7 - 4\sqrt{3}\).