Question

help medal and fan

Answer 1

I worked this out with you already?

Answer 2

http://openstudy.com/users/sar12389#/updates/54ade2fbe4b0981c990931c0
q

Answer 3

if it is not completely and totally obvious because you are not used to using this notation,
write it all out
then you will go "doh"

Answer 4

\[1^2+2^2+3^2+4^2+5^2-(1^2+2^2+3^2)\]

Answer 5

subtract, all that is left is \(4^2+5^2\)

Answer 6

That's an interesting way to look at it too.