Sum of to integers must be less than two numbers
m*n=m+m+m+...... n times (if m>n)
Now,this can be written as
m*n=m+n+(m-n) +m+m.......n terms
ie,
Product of two numbers = sum of two numbers + something positive (as m-n>0)
Hence, product of two numbers is always greater than sum of two numbers if both numbers are greater than 1