Find the sum of digits in decimal form of the number (999...9)^3.
(There are 12 nines)
Find the sum of digits in decimal form of the number (999...9)^3.
(There are 12 nines)
HINT:
$999999999999^3=$
$(1000000000000-1)^3=$
$1000000000000^3-3\cdot1000000000000^2+3\cdot1000000000000-1$