SOLUTION: Consider the following proposition: There are no integers a and b such that b^2 = 4a + 2. (a) Rewrite this statement in an equivalent form using a universal quantifier by comple

Algebra.Com
Question 494495: Consider the following proposition: There are no integers a and b such that
b^2 = 4a + 2.
(a) Rewrite this statement in an equivalent form using a universal quantifier
by completing the following:
For all integers a and b,....
(b) Prove the statement in Part (a).

Answer by richard1234(7193)   (Show Source): You can put this solution on YOUR website!
You could say something like, "For all integers a and b, b^2 is never equal to 4a+2."

For any integer b, b^2 is congruent to either 0 or 1 modulo 4. 4a+2 is always 2 modulo 4. If b^2 and 4a+2 were equivalent mod 4, then they could be equal but they're different mod 4, so they can never be equal.

RELATED QUESTIONS

1. Whenever we encounter a new proposition, it is a good idea to explore the proposition (answered by richard1234)
Assume that the following 4 logical propositions are all true : 1. (A → B) ∧ (answered by jim_thompson5910)
Determine the truth value of the following statement. If n = 4k + 1 for a natural k,... (answered by robertb)
a,b and c are such that b^2=4a+4c find the value of... (answered by solver91311)
Assume that the following 4 logical propositions are all true : 1. A → B 2. C... (answered by jim_thompson5910)
I am not sure if I am in the right section. If I am Can I get a little help with this... (answered by swincher4391)
Consider the following statement: Let f be a function, such that for all a and b in... (answered by ikleyn)
Show by an example that the following statement is false in general for integers a,... (answered by AnlytcPhil)
Show by an example that the following statement is false in general for integers a, b,... (answered by stanbon)