The number $(\sqrt{2}+\sqrt{3})^3$ can be written in the form $a\sqrt{2} + b\sqrt{3} + c\sqrt{6}$, where $a$, $b$, and $c$ are integers. What is $a+b+c$?
The number \((\sqrt{2}+\sqrt{3})^3\) can be written in the form \(a\sqrt{2} + b\sqrt{3} + c\sqrt{6}\), where \(a\), \(b\), and \(c\) are integers. What is \(a+b+c\)?
The number (√2+√3)³ can be written in the form a√2+b√3+c√6, where a, b, and c are integers. What is a+b+c?
i put three forms of the same question
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The number (√2+√3)³ can be written in the form a√2+b√3+c√6, where a, b, and c are integers. What is a+b+c?
\((\sqrt2+\sqrt3)^3=(\sqrt3)^3+3(\sqrt3)^2(\sqrt2)+3(\sqrt3)(\sqrt2)^2+(\sqrt2)^3\\ \)
Now expand it out and get the answer for yourself. If you have new problems with this question then let us know.
Yes thanks for posting clearly.
Here is the version I would have liked best
\(\text{The number }\;(\sqrt{2}+\sqrt{3})^3 \text{ can be written in the form }\\a\sqrt{2} + b\sqrt{3} + c\sqrt{6}, \text{ where $a$, $b$, and care integers. What is a+b+c ?}\)
I like this version best becasue it is the easiest to copy and to work on.
I'll post a solution:
We just apply the sum of cubes formula, so, we get \(\left(\sqrt{2}\right)^3+3\left(\sqrt{2}\right)^2\sqrt{3}+3\sqrt{2}\left(\sqrt{3}\right)^2+\left(\sqrt{3}\right)^3\) .
We just simplify this and add like terms, to reach, \(11\sqrt{2}+9\sqrt{3}.\)
From here, we know that \(a=11, b=9, c=0\) , thus \(11+9+0=\boxed{20}.\)