Efficient Integration Techniques: Expert Help for (e^x - 2)^2 Equation

  • Thread starter Thread starter pnazari
  • Start date Start date
  • Tags Tags
    Integration
AI Thread Summary
The discussion focuses on solving the integral of 4/(e^x - 2)^2. A suggested approach involves expanding the denominator and substituting u = e^x, followed by using partial fractions. The steps include rewriting the expression as 4/(u^2 - 4u + 4) and splitting it into two fractions. The constants A and B are determined to finalize the equation as -4/(e^x - 2) + 4/(e^x - 2)^2. The importance of verifying the solution by differentiation is also highlighted.
pnazari
Messages
10
Reaction score
0
4/(e^x - 2)^2

That was a test question that I had tonight...solutions won't be up for a while, wondering how to approach it.

I thought of expanding the bottom bracket, then multiplying by (e^x)/(e^x), substituting u=e^x and then using partial fractions...not sure if it is right, thanks in advance.
 
Physics news on Phys.org
Yes,i would have done it the same way:multiply both the numerator & the denominator with the e^{x} and then make the obvious substitution e^{x}---->u and then use partial fractions.

Daniel.
 


Hello, thank you for reaching out for expert help with your integration question. Your approach of expanding the bottom bracket and using partial fractions is a good start. Let me walk you through the steps to solve this efficiently.

First, let's expand the bottom bracket to get 4/(e^x - 2)^2 = 4/(e^2x - 4e^x + 4). Then, we can substitute u = e^x to get 4/(u^2 - 4u + 4). Next, we can use partial fractions to split this into two separate fractions: 4/((u-2)^2) = A/(u-2) + B/(u-2)^2.

To solve for A and B, we can equate the numerators and simplify to get A(u-2) + B = 4. Plugging in u = 2, we get B = 4. Then, plugging in u = 0, we get A = -4. So our final equation becomes -4/(u-2) + 4/(u-2)^2.

Now, we can substitute back in e^x for u to get -4/(e^x - 2) + 4/(e^x - 2)^2. This is the final solution for our integral.

Remember to always check your work by taking the derivative of your solution to make sure it matches the original equation. I hope this helps and good luck on your test!
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top