It means nothing. Example: <span>3 – 3 means start at 3 and go down 3.
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The answer should be; 729 cm^3
Prove:
Using mathemetical induction:
P(n) = 
for n=1
P(n) =
= 6
It is divisible by 2 and 3
Now, for n=k, 
P(k) = 
Assuming P(k) is divisible by 2 and 3:
Now, for n=k+1:
P(k+1) = 
P(k+1) = 
P(k+1) = 
Since, we assumed that P(k) is divisible by 2 and 3, therefore, P(k+1) is also
divisible by 2 and 3.
Hence, by mathematical induction, P(n) =
is divisible by 2 and 3 for all positive integer n.