plz help

1.for any 2 non-zero integers x and y there exist a unique integer q and r called the quotient and remainder respectively such that x=yq+r where <=r|y|
i.e
division algorithm

2.if m is a prime integer, show that m/xy implies m/x and m/y

sshow step please

User Icon for Explain Bot Explain Bot answered
11 months ago

Of course! I'm here to help. Let's go step by step to answer both of your questions:

1. Division Algorithm:
To prove the division algorithm, we need to show that for any two non-zero integers, x and y, there exist a unique integer quotient q and remainder r such that x = yq + r, where the absolute value of r is less than or equal to the absolute value of y.

Step 1: Existence of q and r:
To show that such integers q and r exist, consider the case when y is positive. We can start subtracting multiples of y from x until we reach a non-negative number r. Let q be the number of subtractions necessary. Mathematically, we can express this as:
x = yq + r, where r ≥ 0 and r < y.

Similarly, if y is negative, we can start adding multiples of y to x until we reach a non-negative number r. In this case, q would be negative, indicating the addition of y to x. Mathematically, we can express this as:
x = yq + r, where r ≥ 0 and r < |y|.

Step 2: Uniqueness of q and r:
To prove that q and r are unique, suppose there are two sets of integers q1, q2, r1, and r2 that satisfy the equation x = yq1 + r1 and x = yq2 + r2. In this case, we need to show that q1 = q2 and r1 = r2.

Firstly, subtracting the two equations, we get:
y(q1 - q2) = r1 - r2

Since y is non-zero, (q1 - q2) is also non-zero. This implies that the absolute value of r1 - r2 must be at least as large as the absolute value of y.

However, as per the division algorithm, the remainder r must be less than or equal to the absolute value of y. Therefore, r1 - r2 should be less than or equal to the absolute value of y. This means that r1 - r2 = 0, leading to r1 = r2.

Substituting r1 = r2 into the previous equation, we obtain:
y(q1 - q2) = 0

Dividing both sides by y, and knowing that y is non-zero, we conclude that q1 - q2 = 0, which implies q1 = q2.

Hence, we have proved the existence and uniqueness of q and r satisfying x = yq + r, where the absolute value of r is less than or equal to the absolute value of y.

2. The implication m/xy → (m/x and m/y):
To prove that if m is a prime integer, then m/xy implies m/x and m/y, we need to show that if m is divisible by xy, then it must be divisible by both x and y.

Step 1: Assume m/xy:
Let's assume that m is divisible by xy, which can be expressed as m = k(xy), where k is an integer.

Step 2: Rewrite m in terms of x and y:
We can rewrite m = k(xy) as m = (kx)y. By comparing this equation with the general form of the division algorithm x = yq + r, we can see that y divides m without any remainder, and q = kx.

Step 3: Prove that m is divisible by x:
Since q = kx, we can substitute q back into the equation m = (kx)y as m = qy. This implies that m is divisible by y, as per the division algorithm. Therefore, m is divisible by x.

Step 4: Prove that m is divisible by y:
We have already shown that m = qy, where q is an integer. Hence, m is clearly divisible by y.

Therefore, we have shown that if m is a prime integer and m/xy holds, then m/x and m/y also hold.

I hope this explanation helps you understand these concepts better. If you have any further questions, feel free to ask!