Studying for a test, help would be appreciated. Suppose you wish to prove P righ
ID: 3119571 • Letter: S
Question
Studying for a test, help would be appreciated.
Suppose you wish to prove P rightarrow Q using the contrapositive method. Suppose P and deduce Q. Suppose ~ P and deduce ~ Q. Suppose ~ Q and deduce ~P. Suppose ~ P and ~Q. Suppose you are trying to prove the following Proposition by using direct proof: Proposition 1: If n is a positive integer such that n 2 mod 4 or n 3 mod 4, then n is not a perfect square Which of the following should be the first sentence of your proof. Suppose n is a positive integer such that n 2 mod 4 or n 3 mod 4. Suppose n is a positive integer such that n 2 mod 4 and n 3 mod 4 Suppose n is not a perfect square. Suppose n is a perfect square.Explanation / Answer
1. (C)
Suppose ~Q and ~P
Because to show P implies Q we need to show not Q implies P.
2. (D)
3. (D)
For contrapositive we start with negation.
4. (A)
Because eventually you have to finish at the required result.
5. (C)
6. (B)
Suppose x^5-4x^4+3x^3-x^2+3x-2 > 0 then x>0 which is contradicting.
7. (B)
Same as above
8. (B,C,D)
All follow congruence rule
a = b mod (c)
Implies a-b is divisible by c
9. (A)
Because 14 divides a-b hence multiples of 14 also divide a-b
10. (B)