Short trick:
(L2+L/2)|0R1xR2
Multiply 23 and 22
Here left digit of both 23 and 22 is 2. and sum of right digits is 5(3+2).
therefore L= 2, R1=3 and R2=2
Solution:
(L2+L/2)|0R1xR2
=22+2/2|03x2
=4+1|06
=5|06
=506
Note: If L is ODD then use ’5’ instead of ’0’ in short trick
Lets Multiply 32 and 33
Here left digit of both 32 and 33 is 3. and sum of right digits is 5(2+3) but left digit is ODD.
therefore L= 3, R1=2 and R2=3.
Solution:
(L2+L/2)|5R1xR2
=32+3/2|52x3
=9+1|56
=10|56
=1056