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question:Given that the domain of the function f(2^{x}) is [0,1], what is the domain of f(log_{2}x)? A: [0,1] B: [1,2] C: [2,4] D: [1,0]

answer:Since the domain of f(2^{x}) is [0,1], 0 leqslant x leqslant 1, 1 leqslant 2^{x} leqslant 2, Hence, in f(log_{2}x), let 1 leqslant log_{2}x leqslant 2, Solving it gives 2 leqslant x leqslant 4, Therefore, the answer is boxed{text{C}}. From the domain of f(2^{x}) being [0,1], we can derive that 1 leqslant 2^{x} leqslant 2, which leads to 1 leqslant log_{2}x leqslant 2 in f(log_{2}x), from which we can find the domain of f(log_{2}x). This problem tests the understanding of the domain of a function and how to find it, as well as the operations of exponential and logarithmic functions. It is a basic question.

question:Compute the domain of the function f(x) = frac{1}{lfloor x^2 9x + 20 rfloor}.

answer:To compute the domain of f(x), we need to find when lfloor x^2 - 9x + 20 rfloor is not 0 because division by zero is undefined. The discriminant of the quadratic x^2 - 9x + 20 is computed as: [ 9^2 - 4(1)(20) = 81 - 80 = 1 > 0 ] This indicates that the quadratic has real roots. Now, solve x^2 - 9x + 20 = 0 by factoring: [ x^2 - 9x + 20 = (x-4)(x-5) = 0 ] Thus, x = 4 and x = 5 are roots. Next, find the interval where this quadratic is less than 1: [ x^2 - 9x + 20 < 1 quad rightarrow quad x^2 - 9x + 19 < 0 ] Factoring x^2 - 9x + 19: [ x^2 - 9x + 19 = (x - 4.5)^2 - 0.25 < 0 ] Take the square root: [ (x - 4.5)^2 < 0.25 quad rightarrow quad -0.5 < x - 4.5 < 0.5 ] [ 4 < x < 5 ] Thus, x^2 - 9x + 19 is negative between 4 and 5, meaning lfloor x^2-9x+20 rfloor = 0 in this interval. The domain of f(x) excludes (4,5), where the floor of the quadratic is 0. Therefore, the domain of f is: boxed{(-infty, 4] cup [5, infty)}

question:Given the universal set U={1, 3, x^22x}, and A={1, |2x1|}, if complement_U A={0}, does such a real number x exist? If it exists, find x; if it does not exist, explain why.

answer:Since complement_U A={0}, it means 0 in U and 0 notin A. This implies that the equation x^2-2x=0 holds true. Solving this equation, we get x_1=2 and x_2=0. When x_1=2, we have |2x-1|=3 in A, which is consistent with the problem statement. When x_2=0, we have |2x-1|=1. In this case, set A does not satisfy the condition of having distinct elements, so x_2=0 is discarded. Therefore, such a real number x exists, and it is boxed{x=2}.

question:Mobius is the fastest mule in Italy. She can run at a top speed of 13 miles per hour when she is without any load to carry, and she can travel at 11 miles per hour as her top speed when she carries a typical load. She travels the 143 miles from Florence, Italy to Rome, Italy at top speed while carrying a typical load, then returns to Florence at her usual top speed without carrying a load. The trip takes 26 hours. How long are her rest stops during each half of the trip?

answer:First, let's calculate the time it takes for Mobius to travel from Florence to Rome with a typical load at a top speed of 11 miles per hour. Time = Distance / Speed For the trip to Rome with a load: Time with load = 143 miles / 11 mph = 13 hours Now, let's calculate the time it takes for Mobius to return to Florence without a load at a top speed of 13 miles per hour. For the trip back to Florence without a load: Time without load = 143 miles / 13 mph = 11 hours The total time spent traveling at top speed is the sum of the time with load and the time without load: Total travel time = Time with load + Time without load Total travel time = 13 hours + 11 hours Total travel time = 24 hours The trip takes 26 hours in total, so the time spent on rest stops is the difference between the total trip time and the total travel time: Rest stop time = Total trip time - Total travel time Rest stop time = 26 hours - 24 hours Rest stop time = 2 hours Since the question asks for the rest stops during each half of the trip, we will divide the total rest stop time by 2: Rest stop time per half = Rest stop time / 2 Rest stop time per half = 2 hours / 2 Rest stop time per half = 1 hour Therefore, Mobius takes a boxed{1-hour} rest stop during each half of the trip.

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