T-40

T minus 40 and suddenly the words are red before me. I don’t recall the substitution for i-cubed and no matter what I do, I have to get this problem right: It’s worth six points, a guaranteed B if I miss it.

I take a breath and flip over one of my scraps of paper and start writing:

cn=n
i=(n2+n)/2
i2=(2n3+3n2+n)/6
i3=(n4+     +n)/4

And here I freeze. I’m missing a term. I remember looking over the substitutions in my notes last night–God, why didn’t I take care to remember i-cubed?–and recall thinking, It’s a test. He can’t possibly do i-cubed, can he?

I close my eyes and try to recreate the page before me. Tentatively, I scribble in “3n2” and hold my breath.

It looks right, so I breathe a sigh of relief and continue.

I stop before I even start. The first term of my problem is i3/n3. If I try to substitute in (n4+3n2+n)/4, I’ll end up with n/4–and that’ll give me an infinite answer! And since the area bounded by x2=1, x=0, x=1, and the x-axis is most certainly not an infinite area, I’ve got it wrong again.

I take another deep breath and look over my work so far. I copied the function correctly. Delta-x is correct, too: (b-a)/n –> (1-0)/n = 1/n. Even Mi is correct! (a+i(delta-x) –> 0+i(1/n) = i/n)

So what am I doing wrong? Where have I made a mistake?

I keep looking. I have to go over everything twice before–BAM!–I suddenly realise what I did wrong: I substituted Mi instead of delta-x, and since i/n definitely does not equal 1/n, there–at last–is my error.

So I erase a couple terms and then rewrite them and finally end up with i-squared, whose substitution I easily recall, and within minutes, I’m done. (:

Now to await the results. And it’s T minus two days for that.

Advertisements

2 thoughts on “T-40

  1. Your brain confuses and terrifies me- but in the good way.

    Tell us your grade when you get it, even if I’m pretty sure it’ll make me envious!

  2. Nick! <3

    I do hope you're doing well, by the way. I miss you. :(

    In any case, although I don't know my exact grade for the final, my final grade for the class was an A. :)

Join the Conversation

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s