ELI5: Explain Like I'm 5

Jacobi method

Jacobi method is a way of solving mathematical problems that involves a system of equations. Imagine you have a bunch of apples and oranges and you want to know how many of each there are, but you don't know the exact numbers. You have some clues, though - for example, you know that the total number of fruits is 10 and the number of apples is 3 more than the number of oranges.

The Jacobi method works by guessing what the answer might be and using that guess to make a new guess that is hopefully closer to the correct answer. You keep repeating this process until you get a guess that is really close to the correct answer (or until you decide it's as close as you need it to be).

To apply the Jacobi method, you start by setting up the equations that describe the problem. In our example, we would have something like:

a + o = 10 (the total number of fruits is 10)
a = o + 3 (the number of apples is 3 more than the number of oranges)

We can rewrite these equations to solve for a and o separately:

a = 10 - o
o + 3 = a

Now we can use our initial guess (for example, a = 5 and o = 5) to make a new guess for each variable by plugging in the current guesses for the other variable:

a = 10 - o (using o = 5 from our initial guess, we get a = 5)
o + 3 = a (using a = 5 from our previous step, we get o = 2)

Now we have a new guess: a = 5 and o = 2. We repeat the process again, using these new guesses to make even better guesses:

a = 10 - o (using o = 2, we get a = 8)
o + 3 = a (using a = 5, we get o = 2)

Our new guesses are a = 8 and o = 2. We keep doing this until we get really close to the correct answer.

The Jacobi method can be used for more complicated problems with more equations and more variables, but the basic idea is the same: make a guess, use that guess to make a new guess, and repeat until you get to the answer you're looking for.