MHB Calculating the Sixth Root of 3

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The discussion focuses on the calculation of the sixth root of 3 using the cube root. The initial approach incorrectly suggested that the sixth root could be derived from multiplying two cube roots of 3. The correct method involves adding the exponents, leading to the conclusion that the sixth root of 3 is actually 3 raised to the power of 1/6. Participants clarified that the proper exponent addition results in 2/3, not 1/6. The conversation emphasizes the importance of correctly applying exponent rules in mathematical calculations.
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Let cbrt = cube rootcbrt{3} x cbrt{3} =

(3)^(1/3) * (3)^(1/3)

3^(1/6) ir sixth root {3}

Correct?
 
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In general, you want to use the following rule:

$$\sqrt[3]{a}\cdot\sqrt[3]{b}=\sqrt[3]{ab}$$

Using exponents, we can get the same result:

$$a^c\cdot b^c=(ab)^c$$

Now, when the base is the same, we can simply add exponents:

$$a^b\cdot a^c=a^{b+c}$$

So, in the given expression, we may write:

$$\sqrt[3]{3}\cdot\sqrt[3]{3}=\sqrt[3]{3\cdot3}=\sqrt[3]{3^2}=3^{\frac{2}{3}}=3^{\frac{1}{3}+\frac{1}{3}}=3^{\frac{1}{3}}\cdot3^{\frac{1}{3}}=\sqrt[3]{3}\cdot\sqrt[3]{3}$$
 
MarkFL said:
In general, you want to use the following rule:

$$\sqrt[3]{a}\cdot\sqrt[3]{b}=\sqrt[3]{ab}$$

Using exponents, we can get the same result:

$$a^c\cdot b^c=(ab)^c$$

Now, when the base is the same, we can simply add exponents:

$$a^b\cdot a^c=a^{b+c}$$

So, in the given expression, we may write:

$$\sqrt[3]{3}\cdot\sqrt[3]{3}=\sqrt[3]{3\cdot3}=\sqrt[3]{3^2}=3^{\frac{2}{3}}=3^{\frac{1}{3}+\frac{1}{3}}=3^{\frac{1}{3}}\cdot3^{\frac{1}{3}}=\sqrt[3]{3}\cdot\sqrt[3]{3}$$

Great but is my answer wrong?
 
RTCNTC said:
Great but is my answer wrong?

Yes, your result is incorrect. :D

You want to add the two exponents to get 1/3 + 1/3 = 2/3.
 
MarkFL said:
Yes, your result is incorrect. :D

You want to add the two exponents to get 1/3 + 1/3 = 2/3.

I forgot that powers are added.
 
Well, what in the world did you do to get "1/6"?
 
Thank you everyone.
 

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