Recent content by nicnicman

Okay thanks for the help everyone

Thanks for the reply. Yeah I know the dx and dy are backwards...it's just the generic formula we were given. Sorry for any confusion. I did expand the expression under the radical and came up with the same expansion you did, but I still could not see a good way to integrate it. That's...

Homework Statement Find the length of the curve x = 3 y^{4/3}-\frac{3}{32}y^{2/3}, \quad -64\le y\le 64Homework Equations Integral for arc length (L): L = \int_a^b \sqrt{1 + (\frac{dy}{dx})^{2}} dx The Attempt at a Solution Using symmetry of the interval and the above integral for arc length...

Okay. I think I've got it. So, \int\frac{dx}{\sqrt{e^{x} + 1}} = \int\frac{2u du}{u(u^{2}-1)} = \int\frac{2du}{(u+1)(u-1)} = \int\frac{du}{u-1} - \int\frac{du}{u-1} = ln|u-1| - ln|u+1| = ln\frac{|u-1|}{|u+1|} where u = \sqrt{e^{x}+1} = ln\frac{\sqrt{e^{x}+1}-1}{\sqrt{e^{x}+1}+1} Thank...

Okay. So, \int\frac{dx}{\sqrt{e^{x} + 1}} = \int\frac{2u du}{u(u^{2}-1)} = \int\frac{2du}{(u+1)(u-1)} And now I'm stuck again.

Homework Statement \int\frac{dx}{\sqrt{e^{x} + 1}} Homework Equations Using u-substitution The Attempt at a Solution Let u = \sqrt{e^{x} + 1} \Rightarrow u^{2} - 1 = e^{x} Then, du = \frac{e^{x} dx}{2\sqrt{e^{x} + 1}} \Rightarrow dx = \frac{2u du}{u^{2}-1} So...

Homework Statement Find a basis for the subset S = {(1, 2, 1), (2, 1, 3), (1, -4, 3)} Homework Equations The Attempt at a Solution I'm not absolutely sure I'm doing this correctly but here is my attempt: First, I put the vectors in S in the rows of a matrix (using multiple...

2n-2

Actually I do need help with b). I don't understand what the problem is asking for.

Sorry for the delay. a) If n = 1 then there are two choices for the first and only element in the domain. So, we have 2 functions if n = 1 If n = 2 then there are two choices for the first element in the domain. Then, since one choice is taken there is one choice for the second element...

Homework Statement How many functions are there from the set {1, 2, . . . , n}, where n is a positive integer, to the set {0, 1} a) that are one-to-one? b) that assign 0 to both 1 and n? c) that assign 1 to exactly one of the positive integers less than n? Homework Equations...

Yeah, now that I look at the problem again I think she just wants us to do every other odd.

Hello everyone, For homework my instructor assigned problem from the book. To show which problems to do she wrote this: 4n + 1 N={1, 2, 3...}. Does this mean problems 5, 9, 13, . . . ? Thanks for any suggestions.

Homework Statement Let S = {2,3,4,5} and consider the poset (S, <=) where <= is the divisibility relation. Which of the following is true? 1. 3 is a minimal element 2. 4 is a greatest element 3. 2 is a least element 4. Both 2 and 3 Homework Equations The Attempt at a Solution My answer: 1 In...

Just answer yes or no. And, you answered my question. I'm pretty sure the answer is yes. Thanks.