The diagram illustrates the formula: 1 + 3 + 5 + ... + (2n - 1) = n² Use the diagram to show that any odd number is the difference of two squares.
How many zeros are there at the end of the number which is the product of first hundred positive integers?
Is it true that $99^n$ has 2n digits and $999^n$ has 3n digits? Investigate!
115 2 = (110 x 120) + 25
that is 13225
895 2 = (890 x 900) + 25
that is 801025
Can you explain what is happening and generalise?