Algorithms Dead Episode 1: Division Under Mod
Do you blindly do operations under mod without knowing why they work? Does it scare you when a problem asks you do print something mod a big number? If so, you should watch Episode 1 of Algorithms Dead!
In it, I talk about why mod operations (addition/subtraction/multiplication) are allowed, why mod inverses work, and what things are safe to do when you store fractions as $$$p*q^{-1}$$$.
It was nice, your channel has many helpful videos,also loved the lecture on Game Theory.
the answer for 8/7(mod 5) = 4 using prime modulo inverse , shouldn't it be 1 ?
The denominator is
7
here, which is congruent to2(mod 5)
.The multiplicative inverse of
2
undermod 5
is3
.So, the expression becomes