Melody

How about you explain?  If you have tried this exercise then you must have some idea. 

What is a tesselation?

Watch this:

You do not need a formula. You just need to understand.

And it would be nice if you answered my questions.

The surface area of anything is the area of all the individual surfaces all added together.

Think about your triangular prism.

How many sides does it have?

What shapes are they?

Are any of the sides the same?

Find the are of each side then add them all together.

I can't' give you are formula unless you tell me the numerals (letters) that you want to use. (and what they stand for)

Good to see that you are having a go but it is not correct.

Look at my first answer and try again.

Attn: Sarajit

A question for you. If it was a 7 by 9 grid what would the answer be?

Thanks very much guest. :)

I'd be interested in seeing an answer (or an outline) to this one too.

I have no idea what DeMoive's theorem is but this is just

\(5*e^{7\pi i}\\=5e^{\pi i } \\= 5(cos\pi+isin\pi)\\=5(-1+0)\\=-5\)

\((343(cis\pi))^{0.\dot3}\\~\\ =343^\frac{1}{3}*e^{\frac{1+2n}{3}\pi i}\\~\\ =7e^{\frac{\pi i}{3}},\qquad 7e^{\frac{3\pi i}{3}},\qquad 7e^{\frac{5\pi i}{3}}\)