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question:Find the smallest positive solution to [tan 2x + tan 3x = sec 3x]in radians.
answer:To solve the given problem, we start by rewriting the given equation using trigonometric identities: [ tan 2x + tan 3x = sec 3x ] We can express sec 3x in terms of cos 3x and use the identity to combine the terms: [ tan 2x = sec 3x - tan 3x = frac{1}{cos 3x} - frac{sin 3x}{cos 3x} = frac{1 - sin 3x}{cos 3x} ] Next, we recall the half-angle identity for tangent: [ tan frac{theta}{2} = frac{1 - cos theta}{sin theta} ] By comparing the forms, we can rewrite our expression as: [ frac{1 - sin 3x}{cos 3x} = frac{1 - cos (frac{pi}{2} - 3x)}{sin (frac{pi}{2} - 3x)} = tan left( frac{pi}{4} - frac{3x}{2} right) ] Therefore, we have: [ tan 2x = tan left( frac{pi}{4} - frac{3x}{2} right) ] Given that the tangent function has a period of pi, we can equate the arguments of the tangent functions and solve for x: [ 2x - left( frac{pi}{4} - frac{3x}{2} right) = n pi ] Solving for x, we find: [ x = frac{(4n + 1) pi}{14} ] To find the smallest positive solution, we consider the smallest integer value for n, which is n=0. Substituting n=0 into the expression for x, we obtain: [ x = frac{(4(0) + 1) pi}{14} = frac{pi}{14} ] Therefore, the smallest positive solution to the given equation in radians is boxed{frac{pi}{14}}.
question:At the MP Donut Hole Factory, Niraek, Theo, and Akshaj are coating spherical donut holes in powdered sugar. Niraek's donut holes have a radius of 5 mm, Theo's donut holes have a radius of 7 mm, and Akshaj's donut holes have a radius of 11 mm. All three workers coat the surface of the donut holes at the same rate and start at the same time. Assuming that the powdered sugar coating has negligible thickness and is distributed equally on all donut holes, how many donut holes will Niraek have covered by the first time all three workers finish their current donut hole at the same time?
answer:The surface area of a sphere is given by the formula A = 4pi r^2. - For Niraek: A = 4 pi times 5^2 = 100pi mm² - For Theo: A = 4 pi times 7^2 = 196pi mm² - For Akshaj: A = 4 pi times 11^2 = 484pi mm² To find when all three workers finish a donut hole at the same time, we compute the LCM of the surface areas: - 100 = 2^2 cdot 5^2 - 196 = 2^2 cdot 7^2 - 484 = 2^2 cdot 11^2 The LCM of 100pi, 196pi, and 484pi is 2^2 cdot 5^2 cdot 7^2 cdot 11^2 pi = 107800pi mm². The number of donut holes Niraek will have covered by this point is frac{107800pi}{100pi} = 1078. Thus, by the first time all three workers finish their current donut hole at the same time, Niraek will have covered boxed{1078} donut holes.
question:Arrange the serial numbers of the following events in ascending order of their likelihood of occurrence: (1) Drawing exactly one yellow ball from a bag containing 1 red ball and 2 yellow balls (2) When oil is dropped into water, the oil floats on the surface (3) Rolling a fair die and getting a number less than 3 on the top face (4) Drawing a card from a deck of cards (excluding jokers) at random, and the card drawn is red (5) Two line segments can form a triangle. A: (2) (1) (3) (4) (5) B: (5) (3) (1) (4) (2) C: (5) (4) (3) (1) (2) D: (5) (3) (4) (1) (2)
answer:(1) The probability of drawing exactly one yellow ball from a bag containing 1 red ball and 2 yellow balls is frac{2}{3}. (2) The probability that oil will float on the surface when dropped into water is 1. (3) The probability of rolling a fair die and getting a number less than 3 on the top face is frac{1}{3}. (4) The probability of drawing a red card from a deck of cards (excluding jokers) at random is frac{1}{2}. (5) The probability that two line segments can form a triangle is 0. Therefore, the correct answer is boxed{text{D}}.
question:the city of Udoev, mayoral elections are conducted as follows. If in a particular round of voting no candidate receives more than half of the votes, another round is held with all candidates except the one with the least number of votes. (No two candidates ever have an equal number of votes; if a candidate receives more than half the votes, they are elected mayor and the election ends.) In each round, each voter votes for one candidate. If their candidate reaches the next round, the voter votes for them again. If their candidate is eliminated, all their voters vote for a single remaining candidate. In the latest election, 2002 candidates were running. Ostap Bender became the mayor, having taken the kth place in terms of the number of votes in the first round. Determine the highest possible value of k if Ostap Bender was elected a) in the 1002nd round; b) in the 1001st round.
answer:Part (a) 1. **Initial Condition**: - There are 2002 candidates initially. - A candidate is eliminated if they have the fewest votes in any round and if no one has more than half the votes. - The process continues until only one candidate remains, collecting all votes from eliminated candidates over successive rounds. 2. **Identifying Constraints**: - If Ostap Bender won in the 1002nd round, then for each of the previous 1001 rounds, some candidates were eliminated. - The least possible value for k is 1. The largest possible value for k is when Ostap Bender was just above the candidate who gets eliminated in the first round, meaning Ostap Bender could have been second to last. 3. **Maximum k Calculation**: - In the worst-case scenario, Ostap Bender can be positioned such that he almost always advances but barely avoids elimination. - Over the rounds, Ostap Bender improves his standing by gathering the votes from eliminated candidates one by one. To determine this maximum possible k, consider he needs to stay-in even until the 1002nd round happens. - To simplify, assume all 2002 candidates tied almost equally: If (k = 2001), this means Ostap would be the second-to-last candidate, but since Ostap wins, he must have survived every round with the minimum number of votes to avoid elimination. 4. **Final Vote Distribution**: - To calculate the number of votes, if each candidate initially gets votes in an almost equal distribution of 10^6, 10^6 + 1, ldots 10^6 + 2001, - When it comes to half the rounds, it means Ostap has outlasted 1001 candidates, collecting their votes one by one. [ text{Total votes Ostap could get:} 10^6 + left(10^6 + 1 + ldots + 10^6 + 1001right) = 1002 cdot 10^6 + frac{1001 cdot 1002}{2} = 10^6 + 501501. ] 5. **Conclusion for Part (a)**: - Ostap's maximum k ensures he missed elimination just until gaining the majority: [ boxed{2001} ] Part (b) 1. **Different Condition**: - Ostap Bender was elected in the 1001st round this time. 2. **Feasibility Check**: - Assume Ostap did not hold the first minimum position (k = 1). - For every more than half the total rounds, there were at least 1001 eliminations. - To win in the exact 1001st round, Ostap must avoid elimination from the start until he gathers a sufficient majority just at the transition between the rounds. 3. **Candidates and Votes**: - Naming the candidates who lost as the least (1001) rounds - If starting minimum, Ostap's placement can only remain viable if each round aggregates lost votes exactly matching his progress until the final positioning. 4. **Final Check**: - Ostap thus takes at each point a position ensuring he does not go beneath the threshold, leading to the conclusion: [ boxed{1} ]