Multiplying functions

We know how to add functions such as X+1 and X+2.

So,how do we multiply these functions?
Don't, mind me saying, its actually dead easy.

so, lets take a function. (A+1). And another function we want to multiply...lets say (A+2)...A is basically any number...

Skills required to continue:
1.2nd grade multiplication ability...
2.Ability to treat letters as numbers...
3. You know what powers are.

 So, lets first set up our problem.

(A+1) x (A+2)
However, conventionally, we can omit the 'x', so the question simply becomes:
(A+1)(A+2)

now...
WATCH, as I unravel the secrets of multiplying this out.

It goes like this
(AxA+2xA+1xA+1x2)

First multiply the first A by the first A in the second function.
Then multiply the first A by the 2 in the second function.
Now, multiply the 1 in the first function by the A in the second function.

Lastly, multiply 1 in the first function by the 2 in the second function.

So, basically, each term in one function has to multiply each of the numbers in the 2nd function.

Sounds complicated.

Then, according to the signs, add or subtract...In this case, its addition as all the numbers involved are positive.
So, completing what we had above.
Answer:
(A^2+3A+2)

If your still confused, I bet you will be, i'll post a bunch of exercises and solve them on the spot!