Question 698161
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You want to simplify:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \sqrt{20\,+\,20\,+\,20}]


Since *[tex \LARGE 20\,+\,20\,+\,20\ =\ 60], *[tex \LARGE \sqrt{20\,+\,20\,+\,20}\ =\ \sqrt{60}]


Then, since the prime factorization of 60 is *[tex \LARGE 2\,\cdot\,2\,\cdot\,3\,\cdot\,5] we can write:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \sqrt{60}\ =\ \sqrt{2\,\cdot\,2\,\cdot\,3\,\cdot\,5}\ =\ 2\sqrt{3\,\cdot\,5}\ =\ 2\sqrt{15}]


Note that a pair of factors inside the radical becomes a single factor outside the radical.


By the way, in plain text, *[tex \LARGE \sqrt{X}] is written sqrt(X).  Your problem here could have been written sqrt(20 + 20 + 20).  Note that the parentheses are ALWAYS necessary to define the radicand.


For further information on the subject of plain text rendering of mathematical expressions, see <a href="http://www.purplemath.com/modules/mathtext.htm">Formatting Math as Text</a>


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
<font face="Math1" size="+2">Egw to Beta kai to Sigma</font>
My calculator said it, I believe it, that settles it
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