00:01
All right, so i see that you need help with this problem, and it says proving extensional statements, prove each extantial statement given below.
00:09
So for a, it says there are positive integers x and y, such that 1 over x plus 1 over y equals or is an integer.
00:26
Okay.
00:31
So i could do one over, because it has to equal an integer.
00:39
So 1 over 2 plus 1 over 2 equals 1, and 1 is an integer.
00:50
And then e, there are three positive integers, x, y, and z that satisfy x squared plus y squared equals z squared.
01:06
So i have to square both for it to equal both.
01:09
So i could do three squared plus four squared equals five squared because nine plus 16 equals 25.
01:23
For the next one, it says there are, for d, disproving extensional statements.
01:37
For each statement below, state, what needs to be proven in order to show that the existential statement is false.
01:44
Your response should be a universal statement.
01:48
So there are positive integers m and n such that the square root of n plus n equals m the square root of m plus the square root of n...