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2d
comment Do we recognize higher degree asymptotes beyond Horizontal and Oblique?
Thanks! Feel free to post a formal answer for approval.
2d
asked Getting hung up on notation for $\frac{d}{dx}e^u$ vs. $\int{e^u}du$
2d
asked Do we recognize higher degree asymptotes beyond Horizontal and Oblique?
Nov
18
accepted DiffEq: When to sub init. cond. to determine +C
Nov
18
comment DiffEq: When to sub init. cond. to determine +C
4 regions b/c Y can not equal 0, and X can not equal (−1/9)1/3. Ok, so 2 dashed lines, if you will. The the solution (a function) can't exist on multiple regions, b/c it would have to cross the boundries
Nov
17
asked DiffEq: When to sub init. cond. to determine +C
Nov
17
comment Integrating DiffEq (and solving for C) yields $C^2=9$ Do you use +3, -3, or both?
So, in this one, once I got to y^2 = .... (Bottom left) I subbed right there, and got 1 solution. But, can't you solve for y = +-sqrt(...) and get 2 solutions? Is there an accepted method? ![enter image description here][1] [1]: i.stack.imgur.com/h3Ods.jpg
Nov
16
comment Integrating DiffEq (and solving for C) yields $C^2=9$ Do you use +3, -3, or both?
ie: Just b/c s is (+), why does that mean the square root must be positive? Is s = 100, $\sqrt{s}$ can still equal -10
Nov
16
accepted How does one integrate Newton's Cooling Law formula?
Nov
16
comment How does one integrate Newton's Cooling Law formula?
Damn, that was fast and accurate. I am rusty.
Nov
16
comment Integrating DiffEq (and solving for C) yields $C^2=9$ Do you use +3, -3, or both?
I'm not sure I follow. Because $s=(4t+C)^2$ that means position (s) HAS to be positive? Therefore $\sqrt{s}$ also has to be (+) ? What is the physical limitation?
Nov
16
asked How does one integrate Newton's Cooling Law formula?
Nov
16
comment Integrating DiffEq (and solving for C) yields $C^2=9$ Do you use +3, -3, or both?
So, both solutions are correct? The proper step is to say that C = +3 and -3 ?
Nov
14
asked Integrating DiffEq (and solving for C) yields $C^2=9$ Do you use +3, -3, or both?
Nov
12
awarded  Tumbleweed
Nov
8
comment Table of values of nDeriv(f(x),x,x) vs. f'(x) gives different results??
Can you review how the TI84+ estimates a derivative? It calc's the secant slope with some threshhold $\varepsilon$? So, it will repeatedly calculate the f'(x) formula you listed above for each point? At x=1 it will use values at f(.999) and f(1.001) ?
Nov
8
comment Table of values of nDeriv(f(x),x,x) vs. f'(x) gives different results??
Ok, so the nDeriv estimation algorithm has error b/c the function is oscillatting so wildly?
Nov
8
accepted Table of values of nDeriv(f(x),x,x) vs. f'(x) gives different results??
Nov
8
comment Table of values of nDeriv(f(x),x,x) vs. f'(x) gives different results??
I may not have been clear. The subject title. I graphed $y=-e^xsin(e^x)$ and $y=nDeriv(cos(e^x),X,X)$ When I looked at the table of values, I saw different numbers!
Nov
8
comment When would you want to model a derivative?
So, the real tome data points. Can you walk me through the thinking again? Lets say I have a real time stock price feed. How do these data values translate into a derivative?