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A multiplicative inverse of 5 mod7 would be a number n ( not a unique one) such that 5n=1
Let's look at the possible numbers
5x1=5mode 7
5x2=10=3 mod 7
5x3=15=1 mod 7 THAT WILL DO IT
3 is the multiplicative inverse of 5 mod 7.
What about the others? 5x4=20, that is -1 mod 7 or 6
5x5=25 which is 4 mod 7
5x6=30 which is -5 or 2 mod 7
How 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.
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What is an example of multiplicative inverse?
A multiplicative inverse is the same as a reciprocal. The multiplicative inverse of x is 1/x. So, the multiplicative inverse of 4 is 1/4; or 7 is 1/7 and of 0.2 is 1/0.2 = 5.
How do you get the multiplicative inverse?
Multiplicative inverses are two numbers whose product is one.Another name for multiplicative inverse is reciprocal. The reciprocal of 2/3 is 3/2. 2/3 X 3/2 = 6/6 = 1. The multiplicative inverse of 7 is 1/7. 7 X 1/7 = 7/7 = 1.
What is the multiplicative inverse of the square root of 7?
Multiplicative inverse is the number that, when multiplied, results in 1, usually 1/# 1/sqrt7 is the inverse, so just rationalize the denominator sqrt7/7 = square root of 7 divided by 7
What is the multiplicative inverse of 2 over 7?
It is 7 over 2 or 3.5
What is the multiplicative inverse of negative 4 over 7?
Negative 7 over 4.
How do you find the multiplicative inverse of a fraction?
Swap the numerator and denominator. For example, the multiplicative inverse of 5/7 is 7/5
What is an example of multiplicative inverse?
A multiplicative inverse is the same as a reciprocal. The multiplicative inverse of x is 1/x. So, the multiplicative inverse of 4 is 1/4; or 7 is 1/7 and of 0.2 is 1/0.2 = 5.
What is the multiplicative inverse of 11 7?
The multiplicative inverse means, what do I multiply my number by to get an answer of 1? ex: The multiplicative inverse of 5 is 1/5. 5 * (1/5) = 1 If your number is a fraction to begin with, flip it over. ex: The mult. inverse of 22/7 is 7/22 (22/7)*(7/22) = 1
How do you turn 5 and 3-7ths into a multiplicative and a additive inverse?
38/7 x 7/38 = 1 = multiplicative inverse 38/7 + -38/7 = 0 = additive inverse
What is the multiplicative of -1?
Assuming the question is about the multiplicative inverse, the answer is, -1. It is its own multiplicative inverse.
What is the inverse of -7 plus 5?
It depends on whether you mean additive inverse or multiplicative inverse.
Multiplicative inverse of a negative number?
The multiplicative inverse is the negative of the reciprocal of the positive value. Thus the multiplicative inverse of -7 is -1/7.
How do you the multiplicative inverse of -3 and 3 seventh?
The multiplicative inverse of -24/7 is -7/24
What is the opposite of -7?
7. The opposite of 7 is -7, so the opposite of -7 is 7.
What is the multiplicative inverse of 3 and a half?
3 and a half = 7/2 so its multiplicative inverse is 2/7.
How do you turn 5 and three sevenths into a multiplicative and a additive inverse?
First convert it into an improper fraction: 5 3/7 becomes 38/7. This is clear because "5" is simply "35/7" (do the math yourself) and 35/7 + 3/7 = 38/7. Additive inverse means "negative." Thus, the "additive inverse" of 38/7 is -38/7. This is true because 38/7 added to -38/7 is 0. That is the definition of an additive inverse. Multiplicative inverse means "reciprocal." Thus, the "multiplicative inverse" of 38/7 is 7/38. This is true because 38/7 multiplied by 7/38 is 266/266, or 1. That is the definition of multiplicative inverse.
How do you find the multiplicative inverse of a whole number?
Divide 1 by the number. The multiplicative inverse of 7 is 1/7, for example.
