# Recent content by ludi_srbin

1. ### I got one problem

Homework Statement integral of csc^3(x)cot(x) Homework Equations I tried using trig identity 1+cot^2(x)=csc^2(x) but I got result where I cancelled my indegrals. The Attempt at a Solution I tried to substitute the above mentioned indentity for csc^2 but I end up getting -cscx +...
2. ### I got two problems

Yup. Today in class I realized how stupid was what I wrote here last night. :blushing: I guess, for some reason, I assumed that because there is that 2x regular cos formula for derivative doesen't apply. Thanks for help. I appreciate it.
3. ### I got two problems

Got the first one too. Thanks for the help. It would help if we actually learned the derivative of cos(2x), but since we didn't and it is nowhere in the book I just assumed we don't need to use it. Well...I certainly do feel better now.:smile:
4. ### I got two problems

I solved the second one but the first one is still killing me.
5. ### I got two problems

Homework Statement I need to find the integral of (e^3x)cos(2x) Homework Equations The Attempt at a Solution I tried using different trig identities for cos(2x) to get a better equation and then tried to do few versions using the integration by parts but they all kept getting...
6. ### Find the derivative of the inverse function

Hmmm...But isn't the range of f(x) (-infinity, infinity)?
7. ### Find the derivative of the inverse function

So I need to find the derivative of the inverse function. I know that f is one-to-one and is continous. Also I know that f'(x)=1+[f(x)]^2. I found the inverse writing my equation like f(x)=x+(1/3)[f(x)]^3 then I switch the variables and get that my inverse function=(1/3)x^3 - x. Then I just take...
8. ### Find ln using differentials.

Alright, so I need to find f(x+h) which would be f(10+0.3), with 0.3 being change in x. Using my notes...I see that I could make my equation look like f(x+h)=f(x+(1+(h/x))), where I would break it so that it looks like f(x+h)=f(x)+f(1+(h/x)). I would then substitute 2.30 for f(x), 0.3 for h and...
9. ### Find ln using differentials.

So the problem says "Taking ln10=2.30 estimate ln10.3 using differentials." The only thing I thought of doing was to set an integral from 1 to 10.3 with 1/x being the equation I integrate, but I'm not sure if that is right. Any help?
10. ### Purdue vs. Illinois

Well, I guess I'll have to become independent and find myself a job quickly. Damn, I told my parents to move to Illinois, but for some reason they like NC. This sucks!
11. ### Purdue vs. Illinois

Well, a just got into the University of Chicago, so I have some decisions to make. I'm still the closest to Illinois, because it has engineering and from what I hear here it is a nice school (I'm Serb so drinking part is a big plus in my world), but you know Fermi Lab and 26 Nober Prize Winners...
12. ### Would a 3.6ish GPA average (maybe it will be higher when i end 12th

Well you seem to be pretty bright guy, so just keep up the good work, and take as many AP courses as you can, because any university likes to see someone work hard. The fact that you came from Colombia and wl help you a lot.
13. ### Would a 3.6ish GPA average (maybe it will be higher when i end 12th

No, I'm Serbian from Bosnia, where we had a nasty civil war. But still our situations are very similar. :smile:
14. ### Would a 3.6ish GPA average (maybe it will be higher when i end 12th

Well it depends. Take my advice because I am in very similar situation as yourself. I came to U.S. 3 years ago, and went from ESL I to AP English IV in 2 years, also went from Algebra I to Calc in about 2 years. My GPA is something like 2.9 WEIGHTED and I still got into the University of...
15. ### Purdue vs. Illinois

Yeah, I will visit both of them by the May 1.