Recent content by Lorek

Homework Statement I have no problem with mathematical formulas, but the graphical problems keep nailing me. For instance A figure which shows four paths along which objects move from a starting point to a final point, all in the same time interval. The paths pass over a grid of equally spaced...

x^2 = x. We're looking for the largest number that that holds true. rearranging we got x^2-x = 0. Plugging in 0.99 to x nets us: 0.99^2 - 0.99 = -0.0099 (not quite 0 but pretty close) Since -0.0099 != 0 that's a problem. .5 ^2 - .5 = -.25 -.25 != 0. (no where near 0). The closest number...

We're looking for the largest number x that is greater than its square. Setting the problem up as x^2 -x and then differentiating says its maximum is at 1/2. The problem I see with that setup is if you take 0.99 and square it you get .9801. (original number larger than its square) 0.99 is...

I don't understand why you need to use \frac{1}{x} instead of x. Its asking for the positive number that is greater than its square at its maximum. x^2 = x Since its number can only be greater than its square as a fraction I used (1/x)^2. Your saying I should set it up as...

Homework Statement Find the positive number that exceeds its square by the largest amount. Obviously this is on the open interval (0,1). Homework Equations The Attempt at a Solution F(x) = ( \frac{1}{n} ) ^2 - n \Rightarrow F'(x) = \frac{-2}{n^3} - 1 = 0 \Rightarrow 1 =...

Ok, I understand that the atomic weight's are weighted averages. I just used the atomic weight because it asks for a ratio between two atoms. As for how to set it up I don't have the slightest idea how to set it up, no example problems to model form, nor solution steps.

The atomic weight of C-12 is 12.011, the atomic weight of C-13 is 13. I divided the weight of C-12 by the weight of the C-13 to get a ratio.

Homework Statement What is the ratio of mass of a 12C atom to a 13C atom The Attempt at a Solution 12.011/13 = .9239230769 Solution given at back of book = .92286