Question
Download Solution PDFWhat is \(\sqrt{17 - 4\sqrt{15}} + \sqrt{8 - 2\sqrt{15}}\) equal to?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven:
The required expression: \(\sqrt{17 - 4\sqrt{15}} + \sqrt{8 - 2\sqrt{15}}\)
Calculation:
\(\sqrt{17 - 4\sqrt{15}}\) = \(\sqrt{(2\sqrt3)^2 + (\sqrt5)^2 - 2 \times 2\sqrt{3}\times \sqrt5}\) = \(\sqrt{(2\sqrt3 -\sqrt 5)^2}\) = \(2\sqrt3 - \sqrt5\)
\(\sqrt{8 - 2\sqrt{15}}\) = \(\sqrt{(\sqrt{3})^2 + (\sqrt{5})^2 - 2 \times \sqrt{3} \times \sqrt{5}}\) = \(\sqrt{(\sqrt{5} -\sqrt{3})^2 }\) = \(\sqrt{5} - \sqrt{3}\)
Now, adding both terms:
\(2\sqrt3 - \sqrt5\) + \(\sqrt{5} - \sqrt{3}\) = \(\sqrt3\)
Therefore, the final answer is option 1.
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