Multiplying out brackets

[Lorian]

Am doing maths coursework and am trying to figure out how to multiply out these brackets:

(0.5n+0.5)(n+2)

If n is 3 then I should get 10, but if I attempt to multiply out the brackets I get 20...

0.5 * n = 0.5n

0.5 * 2 = 1

n * n = n²

n * 2 = 2n

0.5 * n = 0.5n

0.5 * 2 = 1

1.5 + 1 + 9 + 6 + 1.5 + 1 = 20

Where am I going wrong? Cheers

[Argalius]

(0.5n+0.5)(n+2)

is the same as:

(0.5n+0.5)*n + (0.5n+0.5)*2

Then you'll get:

0.5n^2 + 0.5n + n + 1

is:

0.5n^2 + 1.5n + 1

When you put in 3:

0.5*3^2 = 4.5

1.5*3 = 4.5

+ 1

= 10

EDIT: I'm not sure where you went wrong, but I think it's because you divided up 0.5n into 0.5 and n. But it's pretty hard to do it on a PC...

Edited January 28, 2006 by Argalius

[Lorian]

Thanks a lot Arg, been trying to figure that out all morning