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[AbstractTraitorHero]

Oh god  how does parallelograms work I absolutely suck at geometry!

[Vector]

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[AbstractTraitorHero]

The property's of parallelograms and finding the measurements in one as well as stating what parallelogram theorem is used.

[3man75]

I think I get it.

What if you have ln xy^3 square z / t^4?

I know ln is a log of e but I don't know what really means..

[MagmaMcFry]

I won't even begin to try to answer that question until your term has at least the 7 sets of parentheses it deserves. Please, dude, parentheses are not optional by default. There are dozens of ways I could put parentheses in your statement to create fundamentally different terms, and I'm not gonna try to guess which one you mean.

[Vector]

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[Skyrunner]

What kind of things do people learn in Analysis classes?

[Vector]

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[Skyrunner]

Sounds rigorous...

[Vector]

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[frostshotgg]

Speaking of real-valued, is there some measure of reality? Is (-i)^(1/2) less real than just i? As with all math, there has to be some generalized form of real and imaginary numbers.

[3man75]

I'm doing matrices right now and one of the questions in the book is asking to find the function of the form f(t) = at^2 + bt + c that contains the points (-1,2) (0,2) (1,4).

I've substituted the above points into three equations and then create 3x3 matrice.

|1  -1  1|
|0  0   1|
|1  1   1|

Not sure how to get the determinant from this or if I'm suppose to do something else because the book dosen't specify.

[Spehss _]

Got a question on separable differential equations.

Spoiler (click to show/hide)

y(t) is a function of a population infected with a disease at time t days. solution for y(t) is a solution to dy/dt=ky(P-y) where k is a constant and P is total population.

a) Find the solution of the differential equation if y(0)=1.

Solving the separable equation and I get py-y_²=Ae_^kt where A=e_^C.
Steps:
ky(P-y)=k(Py-y_²) = dy/dt

separate into t and y functions, so

1/(Py-y_²)dy = kdt

then integrate,

ln(Py-y_²)=kt+C

remove ln by making everything a power of e.

Py-y_² = e_^kt*e_^C

Then reduce e_^C to another constant, A, to get solution of Py-y_² = Ae_^kt which as far as I can see I can't solve further.

Using the initial value, y(0)=A*e_⁰=A*1 so A=1.

So the solution would be Py-y_²=e_^kt

Does this look correct? I feel like I solved the differential equation wrong since I got a function that I can't seem to solve down to a "y=" statement. This was talked about in class as being a possible outcome of solving separable equations but we didn't talk about using such results in a model like this with an initial value and everything.

[Helgoland]

As someone who is in it right now, it's even more fun when you generalize across all functions. f:Rⁿ->R^m.

I think you mean "all real-valued functions"

Why ' ' ? Let's generalize along the lines of f: M \rightarrow N

[Vector]

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