Question
Asked by:
$5.00 5 Questions - Need help, please!
- From Mathematics: General-Mathematics
- Closed, but you can still post tutorials
- Due on Jul. 28, 2009
- Asked on Jul 27, 2009 at 12:00:34PM
Q:1. For which integers a, b, c does a - b - c = a - (b - c)? Justify your answer.
2. Hosni gave the argument that (a + b) = - a + - b, for all integers a and b. If the argument is correct, supply the missing reasons. If it is incorrect, explain why not.
- (a + b) = (-1)(a + b)
= (-1)a + (-1)b
= -a + -b
3. Using only divisibility tests, explain whether 6,868,395 is divisible by 15.
4. Explain why the product of any three consecutive integers is divisible by 6.
5. A student claims that every prime greater than 3 is a term in the arithmetic sequence whose nth term is 6n + 1 or in the arithmetic sequence whose nth term is 6n - 1. Is this true? If so why?
