How do you prove x and Y are positive integers?

How do you prove x and Y are positive integers?

Since x and y are integers, it follows that either x-y = 1 and x+y = 1 or x-y = -1 and x+y = -1. In the first case we can add the two equations to get x = 1 and y = 0, contradicting our assumption that x and y are positive. The second case is similar, getting x = -1 and y = 0, again contradicting our assumption. q Example: Rational Roots

Is (x^2 + y^2)/(1+xy) a finite positive integer?

Thus the quantity (x^2 + y^2)/ (1+xy) must be either infinite (if xy=-1) or negative (if xy < -1), contradicting that fact that this quantity equals N, which is a finite positive integer. This completes the proof. Notice that if the quantity N = (x^2 + y^2)/ (1+xy) is a negative integer for integers x,y, then N=-5.

How do you find the left side of x2-y2?

Proof. (Proof by Contradiction.) Assume to the contrary that there is a solution (x, y) where x and y are positive integers. If this is the case, we can factor the left side: x2- y2= (x-y)(x+y) = 1. Since x and y are integers, it follows that either x-y = 1 and x+y = 1 or x-y = -1 and x+y = -1.

What is the value of x2-y2 = 1?

There are no positive integer solutions to the diophantine equation x2- y2= 1. Proof. (Proof by Contradiction.) Assume to the contrary that there is a solution (x, y) where x and y are positive integers. If this is the case, we can factor the left side: x2- y2= (x-y)(x+y) = 1.

How do you solve X + Y + Z = 10?

The number of solutions to the equation x + y + z = 10 where x, y, z are positive integers, is given by (k − 1 n − 1), where in this case k = 10, n = 3, giving us (9 2) (2) Since x + y + z = 10, the only way that x = y = z is a solution is if x + y + z = x + x + x = 3 x = 10, but this means x would not be an integer.

How do you factor x 2 – y 2 = 1?

There are no positive integer solutions to the diophantine equation x 2 – y 2 = 1. Proof. (Proof by Contradiction.) Assume to the contrary that there is a solution (x, y) where x and y are positive integers. If this is the case, we can factor the left side: x 2 – y 2 = (x-y)(x+y) = 1.

How do you find the X and z axis of a floor?

The x-axis runs along the intersection of the floor and theleft wall. The y-axis runs along the intersection of the floor and theright wall. The z-axis runs up from the floor toward the ceiling alongthe intersection of the two walls.

Is there a formula to prove there is no rational root?

There is a formula for solving the general cubic equation a x3+ b 2c x + d = 0, that is more complicated than the qaudratic equation. But in this example, we wish to prove there is no rational root to a particular cubic equation without have to look at the general cubic formula. Theorem.

What are some of the first proofs by contradiction?

One of the first proofs by contradiction is the following gem attributed to Euclid. Theorem. There are infinitely many prime numbers. Proof. Assume to the contrary that there are only finitely many prime numbers, and all of them are listed as follows: p1, p2…, pn.