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 64 th 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 That’s enough to feed a large country for 10 years!!

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 = 3 5 You say “ 3 to the power of 5” The two most common index numbers are Squares and Cubes

Some times you have to multiply the same number lots of times. Index (power) notation is a quick way of writing repeated multiplications: x 7= 7 2 is seven squared. Why do you think we call it squared? 7 2 = 7 x 7 (=49) is seven lots of seven. We can think of this geometrically.

We can also think of ‘cubes’ geometrically: This represents: 8 x 8 x 8 We say ‘eight cubed’ 8 3 = 8 x 8 x 8 = 64

This is the symbol for square root This is the symbol for cube root