calculus 2 needed help on problems.....

[DSM4Life]

Can you guys help me out. I am in calc2 and having trouble. I was given the test took it (wasnt good). Well we got to take the test home handed in work on seprate sheet of paper. I wanted to try and do them at home to see if its possble for me to even do the problem. I took it to the calc2 student tutor and it took him 2 hours to figure out 2 problems !!! How am i suppose to do 10 problems in 1 1/2 hrs and it takes this tutor (who is in calc3) longer to do 2 probelms ?!?! anyway long story short i am having problems. CAn you guys check these sample problems out and walk through the steps. If you give me the answer can you explain how you got it, which methods used (sub, interg. by parts and all that fun stuff) ?

 

These are some problems.

1 2x^3 + 5x

Eval. S ----------------

0 x^4 + 5x^2 + 4

 

 

 

dt

S ------------

sqroot-----------

t^2 - 6t + 13

 

 

 

??? Any help i thank you in advance

[ecoli]

I'd try to help you, but I'm having a hard time understanding the problems you wrote. Try rewriting them (in LaTex if possible)

[Tom Mattson]

I took it to the calc2 student tutor and it took him 2 hours to figure out 2 problems !!! How am i suppose to do 10 problems in 1 1/2 hrs and it takes this tutor (who is in calc3) longer to do 2 probelms ?!?!

 

That doesn't mean anything. Calc 3 is more of a continuation of Calc 1 than Calc 2. The fact that he couldn't do the problems quickly is simply an indicator that he is doing different stuff now' date=' and that the summer was long and fun. I would expect that an average Calc 2 student can solve Calc 2 problems better and more efficiently than an average Calc 3 student.

 

As for your problems, I'm with ecoli. Buddy, you've got to learn LaTeX.

 

Let me see if I can decipher these.

 

1 2x^3 + 5x

Eval. S ----------------

0 x^4 + 5x^2 + 4

 

OK, now I'm almost certain that you meant this:

 

[math]\int_0^1\frac{2x^3+5x}{x^4+5x^2+4}dx[/math]

 

dt

S ------------

sqroot-----------

t^2 - 6t + 13

 

And here I *think* you mean this:

 

[math]\int\frac{dt}{\sqrt{t^2-6t+13}}[/math]

 

Tell me if I'm right on those, and we'll go from there.

 

If you want to know how I did that, you can click on the equation and the source code will pop up.

[DSM4Life]

i drew them up in mspaint , a lot easier to understand

[DSM4Life]

lol, yeah thats what i meant. Is that what was meant by "in LaTex if possible"? I am new to site am not sure how to use that.

 

Come on you have to admit that my mspaint is pretty damn good though

 

EDIT :

 

"If you want to know how I did that, you can click on the equation and the source code will pop up."

 

Got you

[Tom Mattson]

OK from your attachment I can tell that I was right. Here we go.

 

[math]\int_0^1\frac{2x^3+5x}{x^4+5x^2+4}dx[/math]

 

This is a rational function, so it should scream "PARTIAL FRACTIONS!" That means you've got to factor the denominator, which factors into 2 irreducible quadratics.

 

Try that, and if you get stuck post what you have and we'll get you un-stuck.

 

[math]\int\frac{dt}{\sqrt{t^2-6t+13}}[/math]

 

You have a quadratic under the radical, which means that you want to do a trig substitution. But you don't have either a sum or difference of squares under there, so you have to complete the square and try to work the radicand into one of the 3 forms that is amenable to trig sub.

 

Try that, and again if you get stuck post what you've got and we'll nudge you.

[Tom Mattson]

lol' date=' yeah thats what i meant. Is that what was meant by "in LaTex if possible"? I am new to site am not sure how to use that.

[/quote']

 

Check this out:

 

Quick LaTeX Tutorial

 

There are some instructions, as well as some sample equations that you can click on. Start by copying other people's equations and making changes to them. That's how everyone gets used to it.