Determine if the congruence has solutions

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In summary, to determine if a congruence has solutions, you must first set up the congruence equation with the given values and use the Euclidean algorithm to find the greatest common divisor. If the greatest common divisor divides the difference between the two sides of the equation, then the congruence has solutions. The Euclidean algorithm is a method used to find the greatest common divisor of two numbers. A congruence can have more than one solution, depending on the pattern of solutions based on the greatest common divisor. If the greatest common divisor does not divide the difference between the two sides of the equation, then the congruence does not have any solutions. There are a few shortcuts for determining if a congruence has solutions
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msimard8
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Homework Statement



Determine if the congruence has solutions. If it does, determine the complete solution

x^11 + 3x^10 + 5x ≡ 2 (mod 11)

Homework Equations





The Attempt at a Solution



i know that 11 | x^11 + 3x^10 + 5x -2

and where ax≡c (mod m) has a solutioon iff gcd(a,m) | c

and that's about it

i also know if x =1...then the gcd(11,9) | 2 ...meaning there is a solution

help
 
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  • #2
The only thing I can think about is checking each number 1-10 to see which has a remainder of 2.
 

FAQ: Determine if the congruence has solutions

How do you determine if a congruence has solutions?

To determine if a congruence has solutions, you must first set up the congruence equation with the given values. Then, use the Euclidean algorithm to find the greatest common divisor of the numbers involved. If the greatest common divisor divides the difference between the two sides of the equation, then the congruence has solutions.

What is the Euclidean algorithm?

The Euclidean algorithm is a method used to find the greatest common divisor of two numbers. It involves continuously dividing the larger number by the smaller number until the remainder is 0. The last non-zero remainder will be the greatest common divisor.

Can a congruence have more than one solution?

Yes, a congruence can have more than one solution. This is because the congruence equation will have a pattern of solutions based on the greatest common divisor. For example, if the greatest common divisor is 4, then the solutions will be 4 units apart.

What if the greatest common divisor does not divide the difference between the two sides of the equation?

If the greatest common divisor does not divide the difference between the two sides of the equation, then the congruence does not have any solutions. This means that the given values do not satisfy the congruence equation and there is no solution that will make it true.

Are there any shortcuts for determining if a congruence has solutions?

There are a few shortcuts for determining if a congruence has solutions. One is to check if the given values are relatively prime, meaning they have no common divisors other than 1. If they are relatively prime, then the congruence has solutions. Another shortcut is to use the Chinese Remainder Theorem, which states that if each pair of congruences in a system has solutions, then the system as a whole has a solution.

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