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    Maximisation problem / costs: Consider a firm with two inputs K and L...

    Consider a firm with two inputs K and L that produce an output Q(K, L). The firm’s cost function is C(K, L) = K + 2L It is required to minimize C(K, L) subject to the constraint Q(K, L) = q where q is a positive real constant. You may assume that the optimization problem has a solution at an...
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    deriving finite difference scheme for partial differential equation.

    Hi, Can anyone help with the last part of this question, I just cannot seem to derive the scheme! \frac{u_{j}^{n+1}- u_{j}^{n-1}}{ 2 \Delta t} - 5 \frac{u_{j+1}^{n} - u_{j-1}^{n}}{ 2 \Delta x } = 0
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    row reducing matrix,

    When looking for a possible new pivot, why do we only search from row k to n in column k? In other words, what unwanted thing could happen if we used a row above row k as the new pivot row? am not really sure why, we choose the next pivot to be below the kth...
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    help numerical analysis

    For any integer value of n, define F(n) as the combined operation count of forward and backsubstitutions and define G(n) as the operation count of gaussian elimination. When n gets larger and larger,why does F(n) grow much more slowly that G(n) does? I have no idea why? can anyone point me in...
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    angular velocity

    1)A light bucket contains a ball of mass m. The bucket is attached to a rigid rod and swung in a vertical circle at a constant angular velocity. The distance from the pivot point to the bottom of the bucket is a. What is the minimum angular velocity of the bucket such that the ball does not...
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    calculation torque help!

    Hello, Can someone please just clarify my notes for me, i really cant understand how my teacher gets j = - cos \phi \hat{\phi}-sin \phi \hat{r} I have attached the question and solution, but i have no idea how to work out j, the unit vector in terms of phi and r, please can someone show...
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    proof by induction help

    Let *^{n}(a) = {a*.......*a } n times thus *^{1} = a *^{2} = a*a *^{3} = a*a*a etc prove by induction that *^{n}a = (a+1)^{n} -1 for all n in N am really having problems understand how to do this, please can someone show a step by step solution guide? so far i...
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    sequence divergence proof

    a_{n} = \sqrt{n} + 2sin (n) let m >0 take N= (2+m)^{2} and let n >N then \geq \sqrt{n} -2 > 2+m-2 = m because n >N \sqrt{n} > \sqrt{N} = 2+m where does N come from ? we want a_{n} > m start with a_{n} = \sqrt{n} + 2sin (n) > \sqrt{n} -2 which exceeds m...
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    convergence / divergence help

    a_{n} = \dfrac{n^{3}}{1+ln(n)} a) for all n ∈ N. Say whether this sequence is divergent, convergent, and/or bounded. i think this sequence is divergent, just from looking at it? b) Give a proof of your answer to part (b). Standard properties...
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    sequence divergence proof

    Can someone please explain this proof to me, I dont understand how N = 4M^{2}
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    epsilon -N proof of a limit help

    Please can someone explain the proof of this one for me, I just dont get it.. I get | n*e^{-n}-0 | < \epsilon
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    epsilon -N proof of a limit help

    really struggling with this question... Determine the limit of this sequences, weather it converges or diverges and prove your limit is the correct one. a_{n} = sin(\frac{2\pi}{n}) the lim as n approaches infinity is 0 so | sin(\frac{2\pi}{n})-0 | <\epsilon sin(\frac{2\pi}{n})...
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    limit problem,

    a_{n} = \frac{2n^{2}+n}{n^{2}+2n} then the limit as n approaches infinity is ? not sure what to do... i tired to factorise and \frac{2n+1}{1+2n} but this gives me 1, the correct answer is 2?
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    supremum and infimum

    Find the supremum, infimum, maximum and minimum of the following sets, or indicate that they don’t exist. not sure about the other three, but is the first one, min = 0 max = 2 inf = does not exits sup = 2?
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    Euclidean Algorithm

    find a value of x between 0 and 77 such that 10x = 1(mod77) I did the algorithm and got 1 = -23 *10 + 3*77 so should the value of x be 54?
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    prime number proof help

    prove that 7 is the only prime p of the form n^{3}-1 for n in the set of natural numbers very lost with this question, I have factored it to however how do i 'prove' that 7 is the only prime number that can be written in this way ? (n^{2}+n+1)(n-1)
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    proof by induction

    prove by induction that 11 | 5^{2n}-3^{n} let f(n) = 5^{2n}-3^{n} /tex] f(1) = 5^{2} - 3 = 22 which is divisible by 11 assume it is true for n =k f(k) = 5^{2k}-3^{k} induction step f(k+1) = 5^{2{k+1}}-3^{k+1} = 5^{2}(5^{2k})- 3(3^{k}) f(k+1) - f(k) =...
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    Proving an equivalence relation

    [A relation is defined on the set of all rational numbers as follows, a~b means that there is a rational number k >0 , such that a = b^{k} prove that ~ is an equivalence relation. on the set of all natural numbers N. Okay so I have to show it is reflective, symmetric and transitive...
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    proof help

    Let f be a polynomial of the form f(x) = x^{n} +C_{1}x^{n-1} + .....C_{n-1}x+c_{n} where each coefficient c_{j} is an integer. Assume that n is greater than or equal to 1, and let \alpha be a rational number such that f(\alpha) = 0 prove that \alpha must in fact be an...
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    linear algebra proof help

    I have attempted part 'a', but have no idead how to do part b or c, any. av + bv = 0 a \lambda v + b \lambda v = 0 \lambda (au+bv) = \lambda 0 = 0 a \lambda u + b \mu v =0 a A u + bAv = A (au+bv)= A0 = 0 Is this making any sense...
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