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Formally, a number n, has an inverse mod p only if p is prime. The inverse of n, mod p, is one of the numbers {0, 1, 2, ... , k-1} such that n*(p-1) = 1 mod p

If p is not a prime then:

if n is a factor of p then there is no such "inverse"; and

if n is not a factor of p then there may be several possible "inverses".

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Q: How do you find the multiplicative inverse of a number mod a number?
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Find the inverse of 4 mod 17?

is it 4 inverse of mod 17 or whole inverse? Whole inverse do not make sence, so, ans for the q is 13.


How do you find pairs of numbers which are equal?

Numbers. i^n = i^(n mod 4). With n = 27, 27 mod 4...


Additive inverse property?

Additive inverse just means that when you add them, it equals 0. So, 1 and -1; 12 and -12; -74 and 74; 0 and -0. It can also be applied to things other than integers: x+12 and -x-12; 2x-3 and -2x+3 (which is the same as 3-2x) Or, if you know anything about modular arithmetic, then: 7+x≡0 (mod 9) and 2; 6-x≡4 (mod 7) and -2


How do you find inverse of matrix in hill cipher technique?

You must study the Linear congruence theorem and the extended GCD algorithm, which belong to Number Theory, in order to understand the maths behind modulo arithmetic.The inverse of matrix K for example is (1/det(K)) * adjoint(K), where det(K) 0.I assume that you don't understand how to calculate the 1/det(K) in modulo arithmetic and here is where linear congruences and GCD come to play.Your K has det(K) = -121. Lets say that the modulo m is 26. We want x*(-121) = 1 (mod 26).[ a = b (mod m) means that a-b = N*m]We can easily find that for x=3 the above congruence is true because 26 divides (3*(-121) -1) exactly. Of course, the correct way is to use GCD in reverse to calculate the x, but I don't have time for explaining how do it. Check the extented GCD algorithm :)Now, inv(K) = 3*([3 -8], [-17 5]) (mod 26) = ([9 -24], [-51 15]) (mod 26) = ([9 2], [1 15]).


How do you find an equation to solve how many hours minutes and seconds are in 7798 seconds?

You want two numbers so you need two formulae. Number of hours = int(7798/60) where int(x) is the integer part of x. Number of minutes = mod(7798, 60) or 7798 - 60*(number of hours) = 7798 - 60*Int(7798/60). Both int and mod are built-in functions in spreadsheets.

Related questions

Using the Euclid's algorithm find the multiplicative inverse of 1234 mod4321?

Using the extended Euclidean algorithm, find the multiplicative inverse of a) 1234 mod 4321


A multiplicative inverse of 5 module 7 is?

A multiplicative inverse of 5 mod7 would be a number n ( not a unique one) such that 5n=1Let's look at the possible numbers5x1=5mode 75x2=10=3 mod 75x3=15=1 mod 7 THAT WILL DO IT3 is the multiplicative inverse of 5 mod 7.What about the others? 5x4=20, that is -1 mod 7 or 65x5=25 which is 4 mod 75x6=30 which is -5 or 2 mod 7How did we know it existed? Because 7 is a prime. For every prime number p and positive integer n, there exists a finite field with pn elements. This is an important theorem in abstract algebra. Since it is a field, it must have a multiplicative inverse. So the numbers mod 7 make up a field and hence have a multiplicative inverse.


What is the multiplicative inverse of 9 in mod26?

3, since 3*9 = 27 = 1 (mod 26)


Find the inverse of 4 mod 17?

is it 4 inverse of mod 17 or whole inverse? Whole inverse do not make sence, so, ans for the q is 13.


What are the applications of det of a matrix?

it is used to find the inverse of the matrix. inverse(A)= (adj A)/ mod det A


How do you find the inverse of 3 mod 7?

If 3 ≡ x mod 7, then x = 7k + 3 for some k.


What's the additive inverse of -7?

We will answers the two questions:1. What is the additive inverse of -72. What's an additive identity.The additive inverse of a number is the number you have to add to the number in order to get 0. (Or more generically speaking, to get the additive identity element of the group or field.) So the additive inverse of -7 is +7. For any real number a, the additive inverse is -a. If z is a complex number, a+bi, then the additive inverse is (-a-bi) since (a+bi)+(-a-bi)=0.The case becomes a little more interesting in fields other than the real or the complex numbers. The integers mod p, where p is a prime, form a finite field. So if we look at integers mod 7, the additive inverse of 5, for example, would be 2 since 5+2=7 which is congruent to 0 in this field.The additive identity in the field of real or complex numbers is 0."Additive identity" means the number you can add to any other number in order to get the same number back. Since -7 + 0 = -7, the additive identity of -7 is 0.In the case of a+bi where i^2=-1, the additive identity is still 0. If it helps you to think of it as 0+0i, that is fine. In the finite field of integers mod p, where p is a prime, we have p as the additive identity. For example, 2 mod 7 is just 2, and if we add 7 it is 9 but that is still 2 mod 7.All of these ideas can be extended to fields of invertible matrices and many other exciting algebraic structures!


How do you find modulus of number in scientific calculator?

The way you find modulus of a number on a scientific calculator depends on the model of calculator. On the TI-86, you use mod (x,y) or x mod y to find modulus.


What is the additive inverse of 3 in mod 8?

Add 5 in mod 8. (You can always subtract 3 in mod 8 as well, eg 5 + 3 = 0; 0 - 3 = 5.)


Wher can you find a magazine for a sears 12 gauge mod?

Need model number


Where can you find a schematic for Stevens mod 311A?

where can i find a schematic for Stevens mod. 311A


What year SW mod 41 serial number TAH6988 was made?

You will have to call S&W to find out.