Cube roots of perfect cubes
key notes :
Finding a cube root of a number is the opposite of cubing a number.
Cubing a number means using it as a factor in repeated multiplication three times. For example, 43 (read as “four cubed”) means 4.4.4.
43= 4.4.4 =64
Finding the cube root of a number is the opposite. The cube root of a number is a number you can cube to get the original number. For example, the cube root of 64 is 4. You can show a cube root with the symbol ∛.
∛64 = 4
Fun fact
when you cube a whole number, you get a number called a perfect cube. For example, 8, 27, and 64 are all perfect cubes. Their cube roots are whole numbers.
- 23 = 2.2.2 =8 —–>∛8=2
- 33 = 3.3.3 =27 —–>∛27=3
- 43 = 4.4.4 =64 —–>∛64=4
Learn with an example
🔥What is the cube root of 1?—
You want to find the cube root of 1, so figure out which number cubed (multiplied by itself, and then multiplied by itself again) equals 1.
The number 1 cubed equals 1.
13=1 . 1 . 1=1
So the cube root of 1 is 1.
🔥what is ∛8 ?
You want to find the cube root of 2, so figure out which number cubed (multiplied by itself, and then multiplied by itself again) equals 1.
The number 2 cubed equals 8.
23=2 . 2 . 2=8
so cube root of 8 is 2.
🔥what is ∛64
You want to find ∛64 , so figure out which number cubed (multiplied by itself, and then multiplied by itself again) equals 64.
The number 3 cubed equals 64.
43=4.4.4=64
so ∛64 is 4.
Let’s practice!
