/sci/ - Science & Math

[Anonymous No.3699115]

God damnit. I've been studying all day. I'm completely exhausted, and I can't think clearly anymore. I only have 6 more problems, but my brain just won't compute. Due at 4am... I can't take a 0 for this.

If anyone out there knows Calculus, this should be easy, and... I would be so grateful.

I'm paying for my college all on my own, at 20k a year. If I fail this class.. I'm throwing away my money. Thanks for looking.

[Anonymous No.3699117]

Problem 2

[Anonymous No.3699120]

Problem 3

[Anonymous No.3699123]

Problem 4

[Anonymous No.3699125]

Problem 5

[Anonymous No.3699130]

Problem 6

[Anonymous No.3699136]

you must be joking

and yes, this shit is easy. just graph them and the answers fall out by themselves, you dumb fuck.

[Anonymous No.3699137]

>>3699115
1 > k > 6

[Anonymous No.3699142]

>>3699137
sorry I did the signs backwards, but the answers are 1 to 6.

[Anonymous No.3699147]

>>3699117
answer is 2

>>3699120
the answer to this one is 42

>>3699123
fuckin easy mode: 47

>>3699125
are you retarded? answer is 1

>>3699130
this one is kinda tough
answer is 4242424242^424242424(75-3822224)/628

[Anonymous No.3699167]

>>3699137

Much appreciated. 1/6 isn't zero.

>>3699147

My brain is just dead. Caffeine has no effect on me, and thinking is something that's out of the option. Eh. Maybe I'll get a second wind in an hour or two.

And btw, I don't know how the fuck I got into calc. My last math class was college algebra, 2 years ago. But I need it for my degree.

[Anonymous No.3699173]

Is this precalc?

[Anonymous No.3699175]

>>3699173

No, this is college calculus. Third week in. I'm struggling. Mostly because of my heave course load and knowledge gaps.

[Anonymous No.3699213]

>>3699120

OP here. Just figured out 3:

4, 4, 4, 20, 4

I guess I'll just have to do more plug and chug. Not bad. Thanks for the help, and harsh encouragement.

[Anonymous No.3699250]

wat the fuck, have you cracked the book open? this is like pre calc stuff.
I had similar questions when i was taking this course. The book we used had samples in a similar fashion.

do more practice problems instead on relying on hw sets alone.

go to office hrs mang

[Anonymous No.3699279]

>>3699250

There are like 2 pages on this in the book... it's not helpful.

I just get snagged on small things. Like in Problem 4. There is a "k" in the first function, but no "k" in the second function. I don't see how "k" in any way effects the second function..

[Anonymous No.3699334]

1. 1<k<6
2. 4<k<8-cos1 ; 0<c<1
3. t<4, V(t)=4 ; t>4, V(t)=20 ; discontinuous at t=4
4. k=12
5. k=81
6. Q(t)=(.4/.65)t , 0<t<.65 ; Q(t)=.4e^(.45(t-.65)) .65<t<infinity

You may want to get a tutor

[Anonymous No.3699338]

>>3699334

If it makes you feel any better.. I felt really awful copying these, and a little more guilty when they were all correct. I really am not this shitty of a student. I graduated HS with 50 college credits, a year early. That might have been my downfall.. left a lot to be learned.

In any case, thank you very much, sir. I will go through tomorrow and figure out how you got all of these answers. I am already in line for a tutor.

[Anonymous No.3699355]

>>3699279
k doesn't affect the second function, but the second function can be used to determine what k is. If the function is continuous, then at x=3, the first function will be equal to the second function:

kx=4x^2

You already know that x=3 under this condition, so plug it in and solve for k:

3k=4(3^2)
3k=4(9)
k=4(3)
k=12

[Anonymous No.3699360]

>>3699334
this bears repeating.
camp in that math tutoring center and do your problem sets with someone there. it's the difference between dropping with a W and getting a B or an A.

[Anonymous No.3699372]

>>3699355

:) Awesome. That makes sense. I feel like a tool. I'm going to sleep this off, and maybe be smarter tomorrow.

[Anonymous No.3699383]

>>3699338
It takes time but you'll get it. Calc 1 has a lot of basic stuff that you'll use in future math and physics classes, so make sure you understand it now before you move on

Here's #5 since it's kinda tricky:

The function is continuous so at x=3, both parts of the parametric equation must be equal:

k=(3x^4 - 9x^3) / (x-3)

If you simply plug in 3 for x you get an indeterminate form 0/0. Factor out the top and see if you can cancel out that x-3 :

(3x^3)(x-3) / (x-3) => 3x^3

Now equate the result with k and plug in x=3

k = 3x^3
k = 3(3^3)
k = 3^4
k=81

[Anonymous No.3699391]

>>3699360
Repeating again.

I went through the same thing, two or three years between my last math class and Calc I. 95% of the time when I went through problems with a tutor or study group I found myself thinking "that was really simple, why the fuck didn't I get that?" A lot of it is training yourself to make intuitive leaps that get hammered into you in precalc.

Don't get discouraged, just get someone in there to show you how to apply what you spend all day studying.

[Anonymous No.3699404]

I bet none of you retards can figure this out.


A student is standing at the edge of a deep well. They drop a rock into the well and hear a splash 3 seconds later. If the rock is falling due to gravity, but the noise travels back at a constant 340m/s.

How long did the rock fall:

How long did the echo take to come back:

How deep is the well: