Mathematics is easy

2. There is a legend that the inventor of the game of chess asked for a
reward linked to powers.
He wanted on grain of rice on the first square of the chessboard, two on
the second, four on the next...all the way to the 64th square. The King
thought this sounded reasonable – until he worked it out!
Can you work out how much rice this was?
It is 264 grains of rice...that is
18446744073709551616
That’s enough to feed a large country for 10
years!!

3. Some times you have to multiply the same number lots of times.
Index (power) notation is a quick way of writing repeated
multiplications:
3 x 3 x 3 x 3 x 3 = 35
You say “ 3 to the power of 5”
The two most common index numbers are
Squares and Cubes

4. Some times you have to multiply the same number lots of times.
Index (power) notation is a quick way of writing repeated
multiplications:
7
7
7 x 7= 72 is seven squared.
Why do you think we call it
squared?
72 = 7 x 7 (=49) is seven lots of
seven.
We can think of this geometrically.

5. We can also think of ‘cubes’ geometrically:
This represents:
8 x 8 x 8
We say ‘eight cubed’
83 = 8 x 8 x 8 = 64

6. A square number has a square root.
Finding the square root is the inverse of squaring a number
A cube number has a cube root.
Finding the cube root is the inverse of finding the cube of a
number
3
8 2
16 4
This is the symbol for
square root
This is the symbol for
cube root

7. You can also use the power / index notation in algebra.
If a number or term is multiplied by itself several times
you use a power to write the expression in a shorter way.
can be written as