Answer:
A. 4 (RootIndex 3 StartRoot 7 x EndRoot) or
![4(\sqrt[3]{7x})](https://img.qammunity.org/2021/formulas/mathematics/middle-school/4m9nzae0dcfab5wrhpsno4a8l459f1bfnt.png)
Explanation:
Given:
A radical whose value is,
![r_1=\sqrt[3]{7x}](https://img.qammunity.org/2021/formulas/mathematics/middle-school/rn3b469s7jezxcob2jpuf5y94v91amuedv.png)
Now, we need to find the like radical for
.
Let the like radical be
.
As per the definition of like radicals, like radicals are those that can be expressed as multiples of each other.
So, if two radicals
are like radicals, then
![r_1 = n * r_2](https://img.qammunity.org/2021/formulas/mathematics/middle-school/2bizf4gf9j1vkmawe895c2dlih29uwecz2.png)
Where, 'n' is a real number.
Here,
![r_1=\sqrt[3]{7x}](https://img.qammunity.org/2021/formulas/mathematics/middle-school/rn3b469s7jezxcob2jpuf5y94v91amuedv.png)
Now, let us check all the options .
Option A:
4 (RootIndex 3 StartRoot 7 x EndRoot) or
![r_2=4\sqrt[3]{7x}](https://img.qammunity.org/2021/formulas/mathematics/middle-school/7z8i3z7nrqarw069qk0ml08hi186y8ljs2.png)
Now, we observe that
is a multiple of
because
![r_2=4* \sqrt[3]{7x}\\\\ r_2=4* r_1..............(r_1=\sqrt[3]{7x})](https://img.qammunity.org/2021/formulas/mathematics/middle-school/s4xkb2o0pwvibx28fxraqyq8ex1oujgyra.png)
Therefore, option A is correct.
Option B:
StartRoot 7 x EndRoot or
![r_2=√(7x)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/j7wobg920az1v4udqki4e039mnwvq7m0oy.png)
As the above radical is square root and not a cubic root, this option is incorrect.
Option C:
x (RootIndex 3 StartRoot 7 EndRoot) or
![r_2=x\sqrt[3]{7}](https://img.qammunity.org/2021/formulas/mathematics/middle-school/jqu4p87cfjxnyf1d0busryfj8zfrij4e5i.png)
As the term inside the cubic root is not same as that of
, this option is also incorrect.
Option D:
7 StartRoot x EndRoot or
![r_2=7√(x)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/qgzzfgcrgbe5ce2r550ad5po5ftbpx14v1.png)
As the above radical is square root and not a cubic root, this option is incorrect.
Therefore, the like radical is option (A) only.