# Recent content by brandy

1. ### Finite Fourier Transform on a 3d wave

Finite Fourier Transform on a 2d wave How does the finite fourier transform work exactly? The transform of f(x) is \widetilde{f}(\lambda_{n}) =\int^{L}_{0} f(x) X_{n} dx If I had a 3d wave equation pde and I applied Finite fourier transform on the pde for z(x,y,t)=X(x)Y(y)T(t)...
2. ### Proof using f(x1,y1)-f(x0,y0)=fx(x*,y*)(x1-x0)+fy(x*,y*)(y1-y0)

1. Homework Statement [/prove f(x1,y1)-f(x0,y0)=fx(x*,y*)(x1-x0)+fy(x*,y*)(y1-y0) prove there exists a point (x*,y*) if fx and fy are all continuous on a circular region and contain A(x0,y0) and B(x1,y1) 2. Homework Equations [b]3. The Attempt at a Solution I'm thinking mean value...
3. ### How do you tell what a vector space will look like from it's spanning set.

I know that, and it's not really my question unless I misunderstand the applications of what you just said. My question pertains to the visible nature of it.
4. ### How do you tell what a vector space will look like from it's spanning set.

I'm having a hard time visualising them. How do you plot vector fields How do you plot spanning sets? How do you tell if something spans a plane, 3d, a line or more dimensions.
5. ### Basic basic javascript form validation. literally need an help

Javascript is in an external file liked by this: <script type="text/javascript" src="myscript.js"></script> in the head tag i have <form name="myform" action="" method="POST" onSumbit="return validateForms()"> and some form stuff and then: <input type="submit" value="Submit"...
6. ### What does 2nd ord pde tell you? like fxx(x,y)

is there a graphical representation of what it looks like?
7. ### Implicit partial differential for unknown function F(x,y,z)=0

1. Homework Statement F(x,y,z)=0 x=a(y,z) y=b(x,z) z=c(x,y) what does \frac{\partial c}{\partial x} \frac{\partial b}{\partial z} \frac{\partial a}{\partial y} equal. 2. Homework Equations maybe you could tell me? 3. The Attempt at a Solution i've spent hours and hours...
8. ### What does 2nd ord pde tell you? like fxx(x,y)

pure and mixed, what do they tell you about a function?
9. ### Wht does this sign mean?

(\frac{\partial z}{\partial x})y the small y, what does it mean. the context this is used in is F(x,y,z) where each variable is a function of the other 2 variables.
10. ### Volume under curve z=1-x^2-2y^2

1. Homework Statement z=1-x^2-2y^2 find volume under curve bounded by the xy plane. is the answer sheet wrong? (see below) why am i struggling so much with this??!?!?! how do i do it? 2. Homework Equations according to other answer sheet, it is pi/sqrt 2 3. The Attempt at a...
11. ### Vector space prove 0u=0

1. Homework Statement prove 0u=0 where u is in the vector space. 2. Homework Equations the 10 various axioms for addition and scalar multiplication. 3. The Attempt at a Solution pretty much just (u+-u)u=0 or (1-1)u=0 1u+-1u=0 and then i get stuck. i can prove that...
12. ### Show its not a group for # where a#b=a+b-ab in the set of all real numbers

*facepalm* thanks!
13. ### Show its not a group for # where a#b=a+b-ab in the set of all real numbers

1. Homework Statement In set theory, i have a two part question, the first is showing that the system S={set of all real numbers( \Re )}, #} where a#b=a+b-ab we have to show that it's not a group. and then find what c is so that the system = { \Re \cap\overline{c}, # } is a group. 2. Homework...
14. ### Why do some people think women suck at science and math?

Re: Why do some people think women "suck" at science and math? i'm a female who studies BA of maths, ive always been good at maths and i actually think im rather good looking. tall, blonde, blue eyes, slender, etc i have guys falling for me quite a fair bit too. But i think theres this...
15. ### 3-10 points why you believe in the theory of evolution and big bang

Can you give me 3-10 points why you believe in the theory of evolution and/or the big bang? this is independant of any other theories. I'd like it numbered. and just brief points, like a topic and brief explanation of why this makes you believe evolution and/or the big bang to be true. I'll...