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How do you solve this math problem?
(2^-1(mod7))
I came across it recently and I have no idea how to solve it. I'm not a math person or anything.
2 Answers
- Anonymous1 decade agoFavorite Answer
The symbol mod means modulo and the idea is that it gives the remainder part of division.
Example:
23 mod 7 = 2 since
23 / 7 is 3 remainder of 2
15 mod 7 is 1 since
15 / 7 is 2 remainder of 1
Usually this is used for integers so this could mean one of two things:
(a) 1/2 mod 7 = 1/2
(b) or the inverse of 2 mod 7 (that is, the number when multiplied by 2 gives a product of 1 after division by 7), which would be 4 since 2*4 = 8 which is 1 mod 7.
I am inclined to believe that it is (b) since again, this is usually used for integers and not decimals or fractions.
