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Hello,

In my Software Testing class, the text said that a graph
with 5 possible paths and up to 18 iterations(loop) could
equal 4.77 Trillion test cases.

Our assignment was to figure out how the author arrived at
that figure.

Well, I didn't get it figured out before the deadline...
but a couple of classmates said it was a Summation problem.

18 on top of the Sigma, 5^i right of the Sigma and
i = 1 on the bottom of the Sigma.

My HP48G has a Sigma (Green shift TAN) but I haven't figured
out how to use it.

Could someone show me how?

Sincerely,

the Klutzy Math Groupie,

Ren

dona nobis pacem

Here are the keystrokes to accomplish this with the equation editor, so it looks just like you'd see in the textbook:

EQUATION (Left-shift ENTER)
SIGMA (Right-shift TAN)
I=1
-> (right arrow)
18
->
5 y^x I
ENTER

That puts the sum on the stack as an algebraic object, which also shows you how to type it in directly without the equation editor.

To then get the sum, use EVAL.

Yippee!

I was paging through the HP48 pdf and when I saw the references
to Equation writer, something in my head said, "it's gotta be
easier than that, it's right there on the keyboard".

Thanks again!

Ren

dona nobis pacem