269,707 views
26 votes
26 votes
9 - Who is correct?Maria stated this: If x3=729then x313=72913Jordan stated this: If x3=729 then x=3729

9 - Who is correct?Maria stated this: If x3=729then x313=72913Jordan stated this: If-example-1
User John Nilsson
by
2.7k points

2 Answers

6 votes
6 votes
Both maria and jordan are correct
User Stefan Breunig
by
2.7k points
19 votes
19 votes
Step-by-step explanation

First of all, it's important to remember the relation between radicals and exponents:


\sqrt[n]{x}=x^{(1)/(n)}

So if we have the following equation:


x^3=729

We can solve it in two ways. On the one hand we can apply a cubic root at both sides:


\begin{gathered} \sqrt[3]{x^3}=\sqrt[3]{729} \\ x=\sqrt[3]{729} \end{gathered}

On the other hand, we can raised both sides to 1/3 which is the same as applying a cubic root:


\begin{gathered} (x^3)^{(1)/(3)}=729^{(1)/(3)} \\ x=729^{(1)/(3)} \end{gathered}Answer

As we saw, both Maria and Jordan are correct, they just used different notations.

User Artisan
by
2.9k points