In: Advanced Math
A topological space X is zero − dimensional if it has a basis B consisting of open sets which are simultaneously closed. (a) Prove that the set C = {0, 1}N with the product topology is zero-dimensional. (b) Prove that if (X, d) is a metric space for which |X| < |R|, that is the cardinality of X is less than that of R, then X is zero-dimensional.
In: Advanced Math
Suppose when searching for a large prime, our first step is to sieve by eliminating the first n primes. How large should n be to speed up our search by a factor of 10? This requires careful thought and inventiveness before doing a computation.
How to approach this: Eliminating all odd numbers speeds up our program by a factor of 2, since we've eliminated half of the choices that are composite. If we also immediately disqualify multiples of 3, then we speed up our program by a factor of 3, since we have eliminated 2/3 of all composites. Check that that argument is correct. Now see what happens when you eliminate all of 2, 3 and 5. Again for 2,3,5,7. Now try to figure out the mathematical result and use it to solve for n.
In: Advanced Math
Are the following statements true or false?
1. Let P(n) be the statement "If any string of length n over {a, b} has more a's than b's, then it has two a's in a row". We can prove this statement is true for all n with n ≥ 2 by proving P(2), P(3), and "for all n: P(n) → P(n+2)".
2. Let P(x) be a predicate with one free variable x of type natural. If I prove P(0), "for all x: P(x) → P(x+2)", and "for all x: P(x) → P(x+3)", I may conclude "for all x: P(x)".
In: Advanced Math
2. An industrial sewing machine uses ball bearings that are targeted to have a diameter of 0.75 inches. The lower and upper specification limits under which the ball bearings can operate properly are 0.74 inches and 0.76 inches, respectively.
Past experience has indicated that the actual diameter of the ball bearings is approximately normally distributed with a mean of 0.753 inches and a standard deviation of 0.004 inches.
What is the probability that a ball bearing is:
a. between the target and the actual mean?
b. between the lower specification limit and the target?
c. above the upper specification limit?
d. below the lower specification limit?
e. Of all the ball bearings, 93% of the diameters are greater than what value?
In: Advanced Math
We can write 13 as a sum of distinct powers of 2: 13 = 8+4+1 = 2 3 +2 2 +2 0 .
• Using strong induction, show every integer can be written as the sum of distinct powers of two.
• Show that every integer has a unique representation as the sum of distinct powers of two. It follows that every integer has a unique binary representation. For instance, 13 is uniquely represented by 1101 in binary
In: Advanced Math
For each of the questions below, write a paragraph using an outside source. Be sure to include a reference of your outside source.
Give a short biography of Alan Turing. In your own words, what is the halting problem?
In: Advanced Math
A dietician is planning a snack package of fruit and nuts. Each ounce of fruit will supply zero units of protein,3 units of carbohydrates, and 2 units of fat, and will contain 40 calories. Each ounce of nuts will supply 2 units of protein,1 unit of carbohydrate, and 4 units of fat, and will contain 50 calories. Every package must provide at least 2 units of protein, at least 7 units of carbohydrates, and no more than 14 units of fat. Find the number of ounces of fruit and number of ounces of nuts that will meet the requirement with the least number of calories. What is the least number of calories?
(a)Let x be the ounces of fruit and y be the ounces of nuts. What is the objective function that must be minimized?
(b)The dietician should use __ ounce(s) of fruit and ___ ounce(s) of nuts. These amounts will have a total of ___ calories
In: Advanced Math
Let p be a prime and d a divisor of p-1. show that the d th powers form a subgroup of U(Z/pZ) of order (p-1)/d. Calculate this subgroup for p=11, d=5; p=17,d=4 ;p=19,d=6
In: Advanced Math
Prove: If A is an uncountable set, then it has both uncountable and countably infinite subsets.
In: Advanced Math
Please show that answer step by step and explain clearly, thx!!!!
5. Does the accuracy of a kNN classifier using the Euclidean distance change if you (a) translate the data
(b) scale the data (i.e., multiply the all the points by a constant), or (c) rotate the data? Explain.
Answer the same for a kNN classifier using Manhattan distance.
In: Advanced Math
In: Advanced Math
Answer all parts of question 1.
1a.) Find the limits, as t approaches both positive infinity and negative infinity, of the solution Φ(t) of the ivp x' = (x+2)(1-x^4), x(0) = 0
1b.) Find the value of a such that the existence and uniqueness theorem applies to the ivp x' = (3/2)((|x|)^(1/3)), x(0) = a.
1c.) Explain why x' + ((sin(t)) / ((e^t) + 1)) * x = 0 cannot have a solution x(t) such that x(1) = 1 and x(2) = -1.
In: Advanced Math
3. Dictator and Ultimatum Games with Fehr-Schmidt Preferences. Now let the two utility functions be given by,
UA = xA − .6 max(xB − xA, 0) − βA max(xA − xB, 0),
UB = xB − αB max(xA − xB, 0).
(a) Suppose that the two agents play a dictator game in which player A is given an endowment of 100 and may transfer any amount s ∈ [0, 100] to player B. The material payoffs are then given by (xA, xB) = (100 − s, s). Compute player A's strategy for all possible values of βA.
(b) Now suppose that the two agents are playing an ultimatum game with an endowment of 100. Write down the set of players, the pure strategy space of each player and the payoff functions.
(c) Calculate B's best response to every offer s ∈ [0, 100].
(d) How does the subgame perfect equilibrium of the game depend on αB and βA?
In: Advanced Math
In: Advanced Math