1.Two Numbers that Differ by 1 (for example. 35 & 34)
If a > b then a x b = a xa – a
If a < b then a x b = axa + a
2.Two Numbers that Differ by 2 (for example. 26 & 28)
a x b = [(a + b)/2] x[(a + b)/2] -1
3.Two Numbers that Differ by 3 (a < b) (for. example 26 & 29)
a x b = (a + 1)2 + (a – 1)
4.Two Numbers that Differ by 4 (For example. 18 & 22)
a x b = [(a + b)/2] x [(a + b)/2] – 4
5. Two Numbers that Differ by 6 (for example. 51 & 57)
a x b = [(a + b)/2] x[(a + b)/2] – 9
1. 6.Two Numbers that Differ by an Even Number: a < b and c = (b – a)/2 (For example 59 & 67)
a x b = [(a + b)/2] x[(a + b)/2] – cxc