math

[Dawgs0916]

This is so random...but my school's tutoring thing is closed, and i have to have these three questions done before midnight...so my question is, is anyone here any sort of decent at finding derivatives?

 

[dback]

I am decent at finding derivatives. Can you post the questions here, or take a picture of the problems and post a picture?

 

[Dawgs0916]

I am decent at finding derivatives. Can you post the questions here, or take a picture of the problems and post a picture?

thanks man. like i dont even understand why 1/x= 1/x^2

http://img222.*************/img222/3513/derivatives.png

Uploaded with *************

 

[SaltwaterServr]

I will tell you this here and now...No matter what you do for the rest of Calculus, Cal II and forward, do everything you can to get a TI-89 Titanium. You could do these in literally 15 seconds total.

Check out TexasCalcultronics on Ebay. They have them occasionally for $108 or so.

It does derivatives and integrations of every conceivable kind. Limits, midpoints, area under a curve, etc. Best calculator out there for under $200.

EDIT

You've must've just hit the chain rule.

The last one you need to remember that e is a constant of something like 2.78, but you won't do anything with it. You take the derivative of -5x multiplied by the derivative of e^-5x. final answer -5e^-5x

Top one is the product rule, second one power rule, I think. More math than I want to attempt at this time of the day. If I get my call back from the person I gave the 89 to, I'll set up the answers for you before midnight.

 

[dback]

I just PM'ed you a link to a PDF.

 

[Dawgs0916]

I will tell you this here and now...No matter what you do for the rest of Calculus, Cal II and forward, do everything you can to get a TI-89 Titanium. You could do these in literally 15 seconds total.

Check out TexasCalcultronics on Ebay. They have them occasionally for $108 or so.

It does derivatives and integrations of every conceivable kind. Limits, midpoints, area under a curve, etc. Best calculator out there for under $200.

EDIT

You've must've just hit the chain rule.

The last one you need to remember that e is a constant of something like 2.78, but you won't do anything with it. You take the derivative of -5x multiplied by the derivative of e^-5x. final answer -5e^-5x

Top one is the product rule, second one power rule, I think. More math than I want to attempt at this time of the day. If I get my call back from the person I gave the 89 to, I'll set up the answers for you before midnight.

Salt, will that calculator actually do all those things, and give it with simplified answers including the variables (x, e, etc)...? But the problem is I will still need to show work on the tests.

Again, thanks so much dback.

 

[Hoofbite]

Man. Calculus was complete hell.

I was so glad the day that crap ended. If you have to go further in calculus, I recommend taking the class over the summer. It's every day so you stay on it and it's only a few months.

 

[Hoofbite]

Salt, will that calculator actually do all those things, and give it with simplified answers including the variables (x, e, etc)...? But the problem is I will still need to show work on the tests.

Again, thanks so much dback.

That calculator will get you the answer but if you need to show work, I don't think it will do the job for ya.

Of course, knowing the answer and working backwards is sometimes helpful.

Then again, when I took calculus they didn't allow calculators for some tests.

Oh, here's a cool site that might help.

www.khanacademy.org

They have tons of videos in all academic areas. Tons of calc videos.

[youtube]XIQ-KnsAsbg&feature=player_embedded[/youtube]

 

[dback]

Dawgs, to follow up on Hoofbite's response, the TI-89 calculator will do the derivatives and integrals for you. The TI-89 does give you the simplified solution, no matter the input. Most instructors will require work to be shown and can usually tell when a calculator answer is written down. I still have my Y2K model Ti-89 and it still works wonders for me when I need to do a quick calculation.

 

[danielofthesaints]

1. Product Rule

f(x) = (3x^2+12)'(x^2-(1/x))+(3x^2+12)(x^2-(1/x))'
d/dx = 6x(x^2-(1/x))+(3x^2+12)(2x+(1/x^2))
(most sites will accept this as the answer, but if you want to further simplify it)
d/dx = 6x^3 -6 +6x^3 +3 +24x +(12/x^2)
d/dx = 12x^3 + (12/x^2) +24x -3
d/dx = 3(4x^3 +(4/x^2) +8x -1)

2. Chain Rule

f(x)=5(x^3-x)^4
(d/dx)5(x^3-x)^4
5(d/dx)(x^3-x)^4
5(4(x^3-x)^3)((d/dx)(x^3-x))
20(x^3-x)^3(((d/dx)x^3)-((d/dx)(x)))
20((x^3-x)^3)(3x^2-1)

3. Chain Rule

f(x)=e^-5x
d/dx(e^-5x)'(-5x)'
(e^-5x)d/dx(-5x)'
(e^-5x)(-5(d/dx)(x)')
= -5e^-5x

That'll be 5 bucks

 

[danielofthesaints]

I wish we could use a TI-89 on an exam. They only allow a scientific calculator in my Calculus and Chem classes at UT-Dallas. Ever since we moved up to Tier 1, they are making everything more difficult. :bang2:

 

[SaltwaterServr]

Man. Calculus was complete hell.

I was so glad the day that crap ended. If you have to go further in calculus, I recommend taking the class over the summer. It's every day so you stay on it and it's only a few months.

I took a Cal 1 class in Summer 2 this past year to get me up to speed. I cannot recommend AGAINST that strongly enough. If they split it up over the entire summer, maybe try it, but mine was one summer session 3hours a day. We lost at least 2/3rds of the class by the second test. I dropped it before the deadline and I wasn't learning jack ****.

Cal 2, got an A.

I did everything with the 89 Titanium. In some instances it will give you the most simplified answers which may not be what the instructor is looking for.

Thing is, I worked all my homework with the 89, reverse engineering the work to get to the answer given by the calculator. If you cannot get the work figured out between the problem and the correct answer, you don't really have a good enough grasp on the algebra involved to get you there.

Calculus in essence, is really not that hard at all. It's the damn algebra that will trip you up.

Thing is too, there may be more than one way to work the problem to get where you are going with the final answer. If the instructor (most likely not a PhD teaching calc at Tech) hasn't specifically barred the use of that model, get it. You're still learning the stuff to get there, it's just using all the tools at your disposal.

My instructor at TSU said about the same thing. She said what's the difference in you buying a calculator versus paying an off-campus tutor to help you? You're paying for the answers in either case, and with the 89 you're teaching yourself the steps to get to the correct final answer.

I wish we could use a TI-89 on an exam. They only allow a scientific calculator in my Calculus and Chem classes at UT-Dallas. Ever since we moved up to Tier 1, they are making everything more difficult. :bang2:

Ebay used to have skins for the 89 that made it look just like an 83 or 84. Not saying, I'm just saying.

I expect a lot of the prohibitions against the 89 come from the fact that you can bury information inside the folders that cannot be erased in a few simple steps. Not to mention you can buy apps online that are really helpful when you're hitting Discrete and DE.

 

[Dawgs0916]

It's actually business calculus, so all this stuff is incorporated heavily into word problems as well, which obviously makes everything worse. Hard when your already intimidated when its questions just like the above...

Daniel, are you on paypal? Haha Thanks for taking the time to work all that out.

Salt, I love the way you think. I am always looking to find a "competitive edge". I'm going to look into getting that calculator asap, and would love to hear more about these apps you speak of. You guys are right that working backwards often helps a lot.

 

[danielofthesaints]

It's actually business calculus, so all this stuff is incorporated heavily into word problems as well, which obviously makes everything worse. Hard when your already intimidated when its questions just like the above...

Daniel, are you on paypal? Haha Thanks for taking the time to work all that out.

Salt, I love the way you think. I am always looking to find a "competitive edge". I'm going to look into getting that calculator asap, and would love to hear more about these apps you speak of. You guys are right that working backwards often helps a lot.

Haha, it's on the house bud. However, if somehow we coincidentally meet at a bar, I will be expecting a beer. :laugh2:

 

[SaltwaterServr]

It's actually business calculus, so all this stuff is incorporated heavily into word problems as well, which obviously makes everything worse. Hard when your already intimidated when its questions just like the above...

Daniel, are you on paypal? Haha Thanks for taking the time to work all that out.

Salt, I love the way you think. I am always looking to find a "competitive edge". I'm going to look into getting that calculator asap, and would love to hear more about these apps you speak of. You guys are right that working backwards often helps a lot.

I was in Calculus for Science and Engineering majors. Lots of load/stress word problems, population dynamics, pharmacology/dosage/metabolism, time and component variability for determining chemical reaction times w/wo catalysts crap. We touched on Differential Equations and Discrete Math for determining minimum replications on various experimental designs.

I had a tough time in Polymer Science early in the semester because the math we were using was DE based stuff using on probability functions to determine step growth formation of polymers from points of variable oligomeric growth potentials. Nasty math. Ugly. You really had to use intuition to kind of work your way through the problem to figure out when the reaction would occur to "X" DPI based on the information given, then work the problem backwards to put the equations together.

I really can't think of an app you'd need for Cal 1. The 89 does every thing regarding limits and derivatives of regular and logarithmic equations. In Cal 2 you might need to find one for midpoint theorem. The ones we pulled out where the engineering load stuff for those of us in Biology/Chem majors. Our tests were long and you never finished, so the apps let you bust through the physics crap to get to the interesting stuff, or rather the stuff you better understood.

 

[danielofthesaints]

I was in Calculus for Science and Engineering majors. Lots of load/stress word problems, population dynamics, pharmacology/dosage/metabolism, time and component variability for determining chemical reaction times w/wo catalysts crap. We touched on Differential Equations and Discrete Math for determining minimum replications on various experimental designs.

I had a tough time in Polymer Science early in the semester because the math we were using was DE based stuff using on probability functions to determine step growth formation of polymers from points of variable oligomeric growth potentials. Nasty math. Ugly. You really had to use intuition to kind of work your way through the problem to figure out when the reaction would occur to "X" DPI based on the information given, then work the problem backwards to put the equations together.

I really can't think of an app you'd need for Cal 1. The 89 does every thing regarding limits and derivatives of regular and logarithmic equations. In Cal 2 you might need to find one for midpoint theorem. The ones we pulled out where the engineering load stuff for those of us in Biology/Chem majors. Our tests were long and you never finished, so the apps let you bust through the physics crap to get to the interesting stuff, or rather the stuff you better understood.

Saltwater, did you take Organic Chem 1 & 2? If you did, do you have any tips on how to prepare, study, approach the class? Any good study resources? I'll be taking Ochem 1 next semester. Thanks

 

[SaltwaterServr]

Saltwater, did you take Organic Chem 1 & 2? If you did, do you have any tips on how to prepare, study, approach the class? Any good study resources? I'll be taking Ochem 1 next semester. Thanks

Chemistry minor, so yeah. Organic is unlike any other chemistry you've dealt with, even compared to the AP stuff they teach in high school now. Soooo, it's like learning a new language of chemistry. The first parts are going to be learning nomenclature, which you'll really need to have a good handle on since it applies to every single Chemistry you'll take beyond it other than true Inorganic.

There is no more of that stoichiometric equations bullcrap, IIRC. You're looking at broader pictures to a degree, and then focusing down on the actual molecule by molecule interactions. You have got to have a good handle on the periodic table and how chemicals interact with each other, because you're taking it to a new level in Organic.

Keep in mind that I took Organic 1 and 2 years ago. I've got four chemistries beyond those two, so they all blend together to a point. I will say this, all of them require a good, hard, fundamental understanding of everything in O1 and 2. No two ways about it.

I wish I still had my books so I could skim through them and tell you what you need to really know ahead of time.

Best way to break it down is O-1 teaches you the basics of the fundamentals of Carbon interactions with other molecules. Hybridizations, conformations, labeling, ketones, alcohols, anhydrides, alkynes, alkenes, etc...

It is really teaching you how to spell, add and subtract in chemistry. That will actually make sense once you hit O-2.

There are some very interesting labs involved if you have the right department chair. The nylon rope trick is neat. It's your first exposure to polymer chemistry, and in reality making nylon rope is the first cousin to making Kevlar. Same interfacial chemistry is involved, even though you have no idea what interfacial chemical reactions are, at this point.

Organic can be a weed-out class for chem and biology majors. The little hottie sitting next to me in Cal 2 changed to Mass Comm because of O-1. Read ahead in the book to get yourself acquainted with where and how the stuff you're learning today is going to be applied in the next class or lab exercises.

In lab, KNOW what the reactions are doing, and why they are doing that instead of something else. Ask if you're not sure because there will be more than one way to put something together. Learn your "roadmaps", although I think that might apply more to O-2. Roadmaps being you start with Chemical A and end with Compound H, how do you get there? There's a dozen ways, some are shorter, some are expensive, all get you to the right answer but you have to know the basic chemistry to make the right turn in Albuquerque.

If you don't study to the point of sweat in Organic 1, you'll bleed to death in Organic 2. Like I said, almost every chemistry other than inorganic is based on Organic 1 and 2.

FWIW, the two chemistries you've taken already are probably referred to as Inorganic 1 and 2. They aren't, they're intro physical chemistry classes that are labeled as inorganic because you can take Intro to Physical Chem later on. Doesn't make sense, really, but you've taken Intro to Intro to Intro Physical Chemistry, not Inorganic. Inorganic is another evil monster in and of itself. I wanted no part of it, and I love me some chemistry.

As an aside for a red blooded American male, you've probably heard on the movies somewhere that you can make some nasty explosives out of cleaners and such under your kitchen sink. Organic 1 and 2 teach you the fundamentals of how to do that. TNT? A quick trip to Lowe's or Home Depot. Really simple chemistry, but there are a few CRITICAL steps you must follow. That's the kind of powerful stuff you'll be dealing with in Organic.

You want to be a smart-***, ask your professor on the first day how you get Spectre Shield instead of a sandwich bag from ethylene.

 

[danielofthesaints]

Chemistry minor, so yeah. Organic is unlike any other chemistry you've dealt with, even compared to the AP stuff they teach in high school now. Soooo, it's like learning a new language of chemistry. The first parts are going to be learning nomenclature, which you'll really need to have a good handle on since it applies to every single Chemistry you'll take beyond it other than true Inorganic.

There is no more of that stoichiometric equations bullcrap, IIRC. You're looking at broader pictures to a degree, and then focusing down on the actual molecule by molecule interactions. You have got to have a good handle on the periodic table and how chemicals interact with each other, because you're taking it to a new level in Organic.

Keep in mind that I took Organic 1 and 2 years ago. I've got four chemistries beyond those two, so they all blend together to a point. I will say this, all of them require a good, hard, fundamental understanding of everything in O1 and 2. No two ways about it.

I wish I still had my books so I could skim through them and tell you what you need to really know ahead of time.

Best way to break it down is O-1 teaches you the basics of the fundamentals of Carbon interactions with other molecules. Hybridizations, conformations, labeling, ketones, alcohols, anhydrides, alkynes, alkenes, etc...

It is really teaching you how to spell, add and subtract in chemistry. That will actually make sense once you hit O-2.

There are some very interesting labs involved if you have the right department chair. The nylon rope trick is neat. It's your first exposure to polymer chemistry, and in reality making nylon rope is the first cousin to making Kevlar. Same interfacial chemistry is involved, even though you have no idea what interfacial chemical reactions are, at this point.

Organic can be a weed-out class for chem and biology majors. The little hottie sitting next to me in Cal 2 changed to Mass Comm because of O-1. Read ahead in the book to get yourself acquainted with where and how the stuff you're learning today is going to be applied in the next class or lab exercises.

In lab, KNOW what the reactions are doing, and why they are doing that instead of something else. Ask if you're not sure because there will be more than one way to put something together. Learn your "roadmaps", although I think that might apply more to O-2. Roadmaps being you start with Chemical A and end with Compound H, how do you get there? There's a dozen ways, some are shorter, some are expensive, all get you to the right answer but you have to know the basic chemistry to make the right turn in Albuquerque.

If you don't study to the point of sweat in Organic 1, you'll bleed to death in Organic 2. Like I said, almost every chemistry other than inorganic is based on Organic 1 and 2.

FWIW, the two chemistries you've taken already are probably referred to as Inorganic 1 and 2. They aren't, they're intro physical chemistry classes that are labeled as inorganic because you can take Intro to Physical Chem later on. Doesn't make sense, really, but you've taken Intro to Intro to Intro Physical Chemistry, not Inorganic. Inorganic is another evil monster in and of itself. I wanted no part of it, and I love me some chemistry.

As an aside for a red blooded American male, you've probably heard on the movies somewhere that you can make some nasty explosives out of cleaners and such under your kitchen sink. Organic 1 and 2 teach you the fundamentals of how to do that. TNT? A quick trip to Lowe's or Home Depot. Really simple chemistry, but there are a few CRITICAL steps you must follow. That's the kind of powerful stuff you'll be dealing with in Organic.

You want to be a smart-***, ask your professor on the first day how you get Spectre Shield instead of a sandwich bag from ethylene.

Appreciate this. They refer to the first two chem classes as Gen Chem 1 & 2 here. Then its Ochem 1&2, biochem, inorganic chem, and physical chem thereafter. Our Gen Chem 1 class weeded our class size from 800+ students to 500+ students, and I'm sure this current semester of Gen Chem 2 will do its proportional job as well. When you are talking about "roadmaps", does that have any relation to reaction mechanisms, elementary reactions, chemical equilibrium, activation energy, catalysts that I'm learning right now?

 

[theogt]

Yay for liberal arts degrees.

 

[Dawgs0916]

Daniel, next time in Dallas, you've got it haha cause I know you wont be recreationally visiting Lubbock any time in your near future, and I don't blame you.