# intergral

1. ### line intergral of scalar field ( piecewise curve)

for the line segment c2 , why did the author want to differentiate dx with respect to dy ? and he gt dx = 0 ? I'm curious why did he didnt do so for C3 , where dy= 0 ..Why didnt he also differentiate dy with dx ? dy/dx = 0 ?
2. ### Beam deflection equation - need help with working

I have an exam in January, and going through some problems in my book I came across this formula with an answer, but no matter what maths rules I use I cannot get the answer given on the next line for x, can someone help please, I need to solve the large equation to get x=?L
3. ### Trig Identity Intergral- have I got this right?

So question is to evaluate this intergral: 8x. cos(4x^2 +3) dx Im getting 4x^2 +C Is that right? two trig identities turn the cos(x) into 1? Thanks for any and all help! Rhys
4. ### Line Intergral (getting wrong answer)

I keep getting -320/3 for some reason for this problem. A bit complicated, but need to know how to do this. Find the line integral where consists of the three line segments from to to to . Enter an exact answer. (Headbang)
5. ### Differentiating intergral of composite function

Hi I'm looking for help with a simple question in calculus. The question is: how do you differentiate the integral of a composite function? Specifically, if what is ? The closest thing to an answer I could find was Leibniz's rule, which suggested the answer should be , but the answer...
6. ### Can someone explain how this intergral gets rewritten

Studying for my maths unit for my part 66 license and my example question has a bit that is massively confusing me and I hope someone with better maths skills than me can help [so that when i do my exam i have a chance of getting this right] The question is this: \int\frac{x-4}{x^2-2x-3} And...
7. ### intergral of e^x / (1-2e^x)^3 dx help

e^x / (1-2e^x)^3 dx i replaced (1-2e^x) with a random letter in my case i used "p" i ended up with the answer: 1 / 4(1-2e^x)² + C however it doesnt look right to me, can anyone confirm if i am right or wrong?
8. ### Definite intergral

Hi, I am solving a problem which involves calculating the surface are of a solid revolution about the x – axis. I have found that the surface area can be given by: A = 2\Pi \int_{-70}^{110}r+\frac{rd}{\sqrt{r^{2}-x^{2}}}\: dx I have done this using the trapezium rule as I know the values of r...
9. ### intergral

the intergral of e^t^2
10. ### intergral equation consiquence..

f,g are continues funtion on [a,b] prove or desprove by counterexample that: if \int_{a}^{x}f(t)dt=\int_{a}^{x}g(t)dt then f=g on [a,b] ? how i tried: i this its correct i transfered to the other side \int_{a}^{x}f(t)dt-\int_{a}^{x}g(t)dt=0 \int_{a}^{x}f(t)-g(t)dt=0 what now? i cant do...
11. ### definite intergral

Find the exact value of \int^{\frac{\pi}{2}}_{\frac{\pi}{6}}\frac{cot^3x}{cosecx}dx
12. ### Double intergral using polar

i'm sorry if this look messy and uni computers does not have latex installed, kindly please help to convert it to latex if possible and thank you in advance Evaluate the following interral using geometrical interpretation I= intergral( intergral( (a^2 -x^2 -y^2)^1/2 dxdy , where R is the disk...
13. ### Challenging subdividng intergral question

After further discussions with his accountant, Mr X is not satisfied that he will make enough profit on this land development using these boundaries. He believes that he can increase his profit by cutting each block of land into two (2) smaller blocks of equal area. In order to do this, he plans...
14. ### surfance intergral question

Hello I need help with a surface integral problem. I don't seem to understand how to approach it. My question is attached Thanks
15. ### More integral help!

So I've been trying to figure out the best way to approach this problem, but so far no luck. (int(x*ln(x))/sqrt(x^2-1) I'm thinking this has something to do with inverse sin, but I am not sure what to substitute... Help please? (Clapping)
16. ### Quadrature Using Legendre Polynomials

I am working on studying for my last Qualifying Exam and ran across a problem that has stumped me. I have seen someone else's work for this, but I am pretty it is wrong. Anyway... The solution I have seen is as follows So my issue is that he didn't really use Legendre polynomials...
17. ### Intergral- Max and min of function problem

Hi there I have a problem to find the maximum and minimum functions of the following, \int e^x (x-3) (x+2) but i am not sure what to do with the terms in brackets in order to find (dy/dx) and then the second derivative; (d^2y/dx^2) in order to determine which values are local...
18. ### Line Intergral

Compute the value of the line integral. integral(y dx + z dy + x dz), where the path to integrate on is the curve of intersection of the two surfaces x + y = 2 and x^2 + y^2 + z^2 = 2(x + y). The curve is to be traversed once n a direction that appears clockwise when viewed from the origin...
19. ### Intergral

Hi, got a question about the intergral of e^x+1/e^x-1 I put u=e^x-1, dx=du/e^x And i am left with the intergral of 1/u+1, which isnt right. Can anyone help me?