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# how do u explain... watch

1. this formula?
(n+2)(n+1)
n2+3n +2
i am confused
2. (Original post by Mittow)
this formula?
(n+2)(n+1)
n2+3n +2
i am confused
(n+2)(n+1)
n*(n+1)+2*(n+1)
n^2+n+2n+2
n^2+3n+2

It's not that difficult, just think in steps. If you think you understand it by now, try to make:

(-n+3)(n-6)

Post the answer, so that we can see that you got it.

BTW: It's friday evening. Shouldn't we be doing something else?
3. Multiply each 'term' in the first bracket by each 'term' in the other bracket, then add them up.

ie. n times n = n^2
n times 1 = n
n times 2 = 2n
2 times 1 is 2

add them up you get n^2 + n + 2n + 2 = n^2 + 3n + 2.
4. thank you
i need to know y i Multiply each 'term' in the first bracket by each 'term' in the other bracket, then add them up.
its is really confusing
can anyone help?
5. (Original post by Mittow)
thank you
i need to know y i Multiply each 'term' in the first bracket by each 'term' in the other bracket, then add them up.
its is really confusing
can anyone help?

because you do. dont question just learn....

love Katy ***
6. sorry!!!!
this is a question in a section of my course work!
7. (Original post by Mittow)
thank you
i need to know y i Multiply each 'term' in the first bracket by each 'term' in the other bracket, then add them up.
its is really confusing
can anyone help?
You are expanding the brackets e.g: Multiply out (1+X)(2+X):

1*2=2
1*X=1X
X*2=2X
X*X=X^2

Then collect like terms:

X^2+3X+2
8. (Original post by way2go)
BTW: It's friday evening. Shouldn't we be doing something else?
..and then it dawned on me, god I suck.
9. (n+2)(n+1)
n*(n+1)+2*(n+1)
n^2+n+2n+2
n^2+3n+2

the reason why you multiply like this is because each number in the bracket must be multiplied by each number in the other bracket
you can also work it out by doing this:

n + 1
n l n^2 n
+ l
2 l 2n 2

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