1. Cube

2. Cube
We know that the word ‘CUBE’ is used in geometry. A cube is a solid figure which has all its sides are equal.
If the side of a cube in the adjoining figure is “a” units, then its volume is given by a x a x a = a3 cubic units. Here a3 is called “a cubed” or “a raised to the power three” or “a to the power 3”.

3. What are cube numbers?
A cube number is a number that is the product of three numbers which are the same This diagram makes this concept clearer:

4. 5 x 5 x 5 -5 x -5 x -5 25 x 5 25 x -5 125 -125 We know that - x - = +
You can also have negative cube numbers Have a look at this:
When we cube 5 we get 125
5 x 5 x 5
25 x 5
125
When we cube -5 we get -125
-5 x -5 x -5
25 x -5
-125
We know that
- x - = +
We know that
+ x - = -
Note :
When an negative number is multiplied by itself an even number of times, the product is positive
When an negative number is multiplied by itself an odd number of times, the product is negative

5. Cube Numbers upto 15 (to be by hearted)11
1331 2 8 12
1728 3 27 13
2197 4 64 14
2744 5
125 15
3375 6
216 16
4096 7
343 17
4913 8
512 18
5832 9
729 19
6859 10
1000 20
8000

6. Try These
Find the value of the following
(i) 43 (ii) (-9)3 (iii)