stupid

  1. S

    Feeling so stupid for being stumped...

    Okay I tried to solve this problem but it seems unsolvable to me, please let me know if I missed anything. There's an object traveling through two mediums, say medium A and medium B. In medium A the object travels at 350% velocity. In medium B the object moves at 500% velocity. It takes 6...
  2. B

    a very stupid question

    hi sorry for this stupid question but my brain is not working im writing a game the user collects coins and gets a point everytime they collect one and the game time is counted in integers the overall score is calculated at the end the player should get a higher score the faster he/she collects...
  3. L

    Simple (and stupid) question

    Guys, just have a small question, might sound stupid but here it goes: If I have 1 - |-3 -4| , my answer would be 1-7 right? Thats what I think but I am not sure. The -7 becomes positive because of the abs. value, but then becomes negative again because of the sign? Any toughts? Thanks a lot...
  4. G

    stuck with statistics! think it wont take long to answer this; im just being stupid!

    hi guys, i am giving in my 12000 word dissertation in 5 days and need to run some tests but completely forgotten how to do it!! i want to prove that there is a relationship between the number of friends a migrant has and how frequently they visit a site to make more friends. this is is the...
  5. U

    Stupid formula, I get the question but not the formula

    So here i am again, yes with another retarde post in most of your eyes but I come here because I need help :( Here is the question. Consider the name "john smith" with j letters for the first name and k letters for the second name and where the space between the name is not part of the name...
  6. S

    Two algebra problems? Yes I am a little stupid and even if you can do one, that's ok!

    1. Show that 21*18^(2x)+36*7^(3x) is divisible by 19 for all positive integers x 2. Find all pairs of odd integers m and n which satisfy the following equation: m+128n=3mn
  7. R

    Am I being really stupid or what? (Differentiation)

    Hi t^{{\alpha}-1} dt When you differentiate that, its not ({\alpha}-1)t^{{\alpha}-2 ? Surely it is just 0 ? Or am I just being completely stupid..
  8. C

    Can't seem to get this stupid continuity problem...

    Hey, Any help on this problem would be appreciated. For some reason I can't for the life of me solve any of these questions when an '=' sign is introduced: f(x) = {8x + 4 x < or = 9 and f(x) = {-4x + c x > 9 The question is : Find the value of 'c' that makes the function...
  9. S

    one of those "stupid" proofs

    Hi all, I have to do this problem according to the first part of the Fundamental Theorem of Calculus. Fundamental theorem of calculus - Wikipedia, the free encyclopedia h(x)= (integral of 0 to x^2) sqrt(1+r^3) dr answer: f(x)=sqrt(1+r^3) h'(x)=f(x) h'(x)=sqrt(1+x^6)* 2x Am I right? I...
  10. autumn

    stupid test question.

    i DO understand how to do this, i just cant remember how to get all of the numbers in the equation in order to solve it. "The population of a town is 10000 people. it grows at a rate of 1.4% per year for four years, what is the growth factor, b, for the equation y=a*bx (x being the small integer...
  11. S

    stupid normal distribution question

    Computing conditional expectation... if I have X1,X2 iid normal with N(0,1) and I want to find E(X1*X2 | X1 + X2 = x) Can I simply say: X1 = x - X2 and thus E(X1*X2 | X1 + X2 = x) = E[ (x - X2)*X2) = E[ (x * X2) - ((X2)^2) ] <=> x*E[X] - E[X2^2] = 0 - 1 = -1 ???
  12. Chokfull

    Probably a stupid question...

    So by the trigonometric identities, \sec \theta = \frac {1} {\cos \theta}, but according to my calculator, \sec 0 = 1.57, and \cos 0 = 1. how can this be, seeing as \frac {1} {1} = 1.57 isnt true??
  13. N

    plot multivariable function - stupid question?

    Is is possible to plot a multivariable funciton? How? Sorry if this is a stupid question, but, as I have read in a forum signature "The only stupid question is the one you don't ask. The only stupid person is the one who pretends to know." (Happy) Thanks.
  14. Fnus

    Stupid simple sine/cosine problem

    Alright, so I have this right-angled triangle and I thought I did it right, but apparently I didn't, so any help would be great appreciated! I wanted to find B, So I just used b / SinB = c /sinC SinB = b / c SinB = sin^-1(38/63) I end up with 37.1, but the answers said I wanted...
  15. D

    Stupid Integral Help

    I need to integrate \int5e^{x}sin\left(2x \right)dx, and I just cannot figure out what the trick is to it. I don't think it's any combination of integration by parts since e^{x} will always stay the same and the other function will oscillate back and forth between sin and cosine, and all that...
  16. L

    stupid question about

    hi, what is the more "mathematical or scientific method to find LCM and HCF? instead of just thinking? I remember short division could do the job, but forget how to do so Hope someone explain me together with the concepts. Thanks!!!
  17. C

    Very stupid continuity question

    Is the function (x^2 - 4)/(x + 2) continous at x=-2 ? I am doubtful because 1. It can be reduced to (X-2) so it is continous everywhere. 2. But on the other hand isnt continuity checked for the exact function without making changes to it? Cos if x=-2 then the original function is not...
  18. X

    Another Stupid Differentiaion Problem

    Hey guys Sorry ...here's another differentiation problem i can't solve ><" ...i asked my friends but they have no clue and since it's the holz my teacher is inaccessible Although an example in the textbook showed a similar question, i can't seem to get the answer with the method shown...
  19. C

    Stupid question...how do I know when I'm done? Solving a polynomial equation

    Am I supposed to solve for x? How do I know where to start, and how do I know when I am done?
  20. B

    This may be a stupid question, but...

    How does (cosh squared x - sinh squared x) / (cosh squared x) equal 1 - ((sinh x / cosh x)^2) Help appreciated!