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Grading truth tables is even more fun!

(So glad I don't have to do those any more!)

it gives me comfort to think that for every assignment you have to do your teacher/professor has to correct some where between 20 and 100 times.

this comfort is taken away when I realize that teachers/professors just get other students to correct assignments for them.

5x^4 - 3x^2 - 2

yeah, i was bored. u got it right, not surprised.

The first paper would be the answer key. Mikes answer isn't right.

if you would check ur mathematics, mike's answer is correct since F(x)=X^5-X^3-2x and F'(x)=5x^4-3x^2-2

But the answer key is wrong, there should not be a prime at the f.

That might just be a paper that has no name on it.

Yeah, you're right--the key, if it is the answer key--is showing the original f(x) in a more compact form, not f'(x). (I used wolframalpha--it's been a long time since college, and I feel like I've already paid my dues.)

--

Furry cows moo and decompress.

ahahah that *sucks* dude

You know, that is sooo true. I just graded an exam, where question two started off by saying "Find the Kinetic and Potential Energy for this system", and then went off into a Lagrangian derivation with coupled modes and various oscillatory frequencies. If they got the Kinetic or Potential energy wrong, that meant working through the rest of their junk to figure out the part marks =(

Rather than have cascading errors, do something like this:

1) find f'(x)

2) a function f(x) has derivative f'(x) = blah.

a) find an interval on which f(x) is increasing

etc. This is an easy way to keep error chains short.

I've always thought this was a good idea. Especially when the assignment is on new material. If you don't give credit for solving the remaining problems correctly then you unfairly hurt the students. If you do, you burden the grader.

I expected the comic to end like this:

a) f'(x) =0

b) 0

c) 0

d) 0

e) everywhere, but never in a strict sense

f) everywhere, but never in a strict sense

5 out of 6 points

you're right that is totally how it should have ended! that's genius

I'd respond below, but then you'd just be looking at me again...

That'd be nice :)

I expected

a)

b) 11856

...

and not "why?" but "how?" :-)

This is how I will always answer calculus questions now. It'll save huge amounts of time, and give me most of the points!

Which just shows that an error early on makes a

big difference.Hey! Make zoid stop looking at me!

Watching ya! ;)

This sucks. I'd been valuating my mom's stuff for sometime - Yeah she was a math teacher, now retired.

Hey, me too! Like minds =)

my prof never gave part marks... he said, if you build a great car that cannot drive, no one will buy it

a f'(x)= 5x^4 - 3x^2 - 2

b f'(7)= 12005-147-2=11856

c f''(x)= 20x^3 - 6x

d f'''(x)= 60x^2 - 6

e increasing when x(sqrt10)/10; decreasing when -(sqrt10)/10 f concave up when x(sqrt10)/10; concave down when -(sqrt10)/10

I couldn't resist. Undone math that I understood.

...And hopefully got right.

Ich für meinen Teil habe ja bereits echt längeren Zeitabschnitt nach dem richtigen Kredit im World Wide Web recherchiert. Bereits lichtvoll ich akkurat auf welchem Weg das entdeckt.

That's easy for you to say...