Arithmetic
Reading the answer back
Cubing the result must return the original number. This is how you confirm a cube root by hand.
The Formula
check = (cube root of x) x (cube root of x) x (cube root of x)
Cubing the result must return the original number. This is how you confirm a cube root by hand.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| r | Cube root | same unit | The answer you produced. |
| check | Verification | same unit | The original number, recovered by cubing. |
| r^3 | Cube of r | same unit | Three copies of r multiplied together. |
What Each Symbol Means
rsame unit
Cube root
The answer you produced.
checksame unit
Verification
The original number, recovered by cubing.
r^3same unit
Cube of r
Three copies of r multiplied together.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate a cube root page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate A Cube Root, filed under Math. Every number the guide produces comes from substituting into this one line.