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In order to obtain the graph of the function y=sin left(3x - frac{pi}{4}right), the graph of the function y=sin 3x should be shifted byA: Shift to the left by frac{pi}{4} unitsB: Shift to the right by frac{pi}{4} unitsC: Shift to the left by frac{pi}{12} unitsD: Shift to the right by frac{pi}{12} units

💡To determine the horizontal shift needed to transform the graph of ( y = sin 3x ) into the graph of ( y = sin left(3x - frac{pi}{4}right) ), we analyze the phase shift of the sine function.The general form of a sine function is ( y = sin(omega x + varphi) ), where ( varphi ) represents the phase shift. A positive phase shift indicates a shift to the right, while a negative phase shift indicates a shift to the left.Given the function ( y = sin left(3x - frac{pi}{4}right) ), we can rewrite it as:[y = sinleft(3left(x - frac{pi}{12}right)right)]This shows that the graph of ( y = sin 3x ) is shifted to the right by ( frac{pi}{12} ) units.

Let log_{4}3=x. Then log_{2}27=kx. Find k.

💡First, I recognize that I'm given two logarithmic equations: (log_{4}3 = x) and (log_{2}27 = kx). My goal is to find the value of (k).Starting with the first equation, (log_{4}3 = x), I can rewrite this in exponential form as (4^x = 3). This means that 4 raised to the power of (x) equals 3.Next, I look at the second equation, (log_{2}27 = kx), and rewrite it in exponential form as well: (2^{kx} = 27). This tells me that 2 raised to the power of (kx) equals 27.I notice that 27 can be expressed as (3^3). Since I already have (4^x = 3) from the first equation, I can substitute this into the second equation. Cubing both sides of (4^x = 3) gives me (4^{3x} = 27).Now, I want to express (4^{3x}) in terms of base 2 because the second equation is in base 2. Knowing that (4 = 2^2), I can rewrite (4^{3x}) as ((2^2)^{3x}), which simplifies to (2^{6x}).So now I have (2^{6x} = 27) from the first equation and (2^{kx} = 27) from the second equation. Since both expressions equal 27, I can set their exponents equal to each other: (6x = kx).Finally, solving for (k) by dividing both sides of the equation by (x) (assuming (x neq 0)), I find that (k = 6).

A rectangular prism box has dimensions length x+5 units, width x-5 units, and height x^2+5x units. Determine the number of positive integer values of x for which the volume of the box is less than 1000 cubic units.

💡Okay, so I have this problem about a rectangular prism box, and I need to find how many positive integer values of x make the volume less than 1000 cubic units. The dimensions are given as length = x + 5, width = x - 5, and height = x² + 5x. Hmm, let me think about how to approach this.First, I remember that the volume of a rectangular prism is calculated by multiplying its length, width, and height. So, I need to write an expression for the volume and then set up an inequality where that volume is less than 1000.Let me write down the volume formula:Volume = (x + 5)(x - 5)(x² + 5x)Hmm, that looks like it can be simplified. I notice that (x + 5)(x - 5) is a difference of squares, so that should simplify to x² - 25. Let me check that:(x + 5)(x - 5) = x² - 5x + 5x - 25 = x² - 25. Yep, that's correct.So now, the volume becomes:Volume = (x² - 25)(x² + 5x)Okay, let me expand this expression. I'll use the distributive property (FOIL method) to multiply these two quadratics.First, multiply x² by each term in the second quadratic:x² * x² = x⁴x² * 5x = 5x³Then, multiply -25 by each term in the second quadratic:-25 * x² = -25x²-25 * 5x = -125xNow, combine all these terms:x⁴ + 5x³ - 25x² - 125xSo, the volume expression simplifies to:V = x⁴ + 5x³ - 25x² - 125xNow, I need to find the values of x for which this volume is less than 1000. So, I set up the inequality:x⁴ + 5x³ - 25x² - 125x < 1000To make it easier to solve, I'll subtract 1000 from both sides to bring all terms to one side:x⁴ + 5x³ - 25x² - 125x - 1000 < 0Now, I need to solve this inequality for positive integer values of x. Since it's a quartic equation, solving it algebraically might be complicated. Maybe I can test integer values of x to see when the expression is less than zero.But before I start plugging in numbers, I should consider the domain of x. The width is x - 5, so x must be greater than 5 to ensure that the width is positive. Otherwise, if x is 5 or less, the width would be zero or negative, which doesn't make sense for a box's dimension. So, x must be greater than 5.Therefore, I'll start testing integer values of x starting from 6 upwards.Let me create a table to keep track of the values:| x | Volume Calculation | Volume Result | Inequality (Result < 1000?) ||---|---------------------|---------------|------------------------------|| 6 | (6+5)(6-5)(6² + 5*6) | Calculate... | ? || 7 | ... | ... | ? || ... | ... | ... | ... |Wait, maybe I should compute the volume for each x step by step.Starting with x = 6:Volume = (6 + 5)(6 - 5)(6² + 5*6) = (11)(1)(36 + 30) = 11 * 1 * 66 = 726726 is less than 1000, so x = 6 is a valid solution.Next, x = 7:Volume = (7 + 5)(7 - 5)(7² + 5*7) = (12)(2)(49 + 35) = 12 * 2 * 84 = 20162016 is greater than 1000, so x = 7 is not a valid solution.Wait, but before I proceed, let me check if I did the calculation correctly for x = 7.(7 + 5) = 12, (7 - 5) = 2, (7² + 5*7) = 49 + 35 = 84. So, 12 * 2 = 24, 24 * 84 = 2016. Yep, that's correct.So, x = 7 gives a volume of 2016, which is more than 1000. So, x = 7 is invalid.Wait, but maybe I should check x = 5 as well, even though the width would be zero. Let me see:x = 5:Volume = (5 + 5)(5 - 5)(5² + 5*5) = (10)(0)(25 + 25) = 10 * 0 * 50 = 00 is less than 1000, but since the width is zero, it's not a valid box. So, x must be greater than 5.Wait, but the problem says positive integer values of x. So, x must be a positive integer greater than 5.Wait, but let me check x = 6 again. Volume is 726, which is less than 1000. So, x = 6 is valid.Now, let me check x = 7, which we saw was 2016, which is more than 1000. So, x = 7 is invalid.Wait, but what about x = 8? Let me check:x = 8:Volume = (8 + 5)(8 - 5)(8² + 5*8) = (13)(3)(64 + 40) = 13 * 3 * 10413 * 3 = 39, 39 * 104. Let me calculate that:39 * 100 = 3900, 39 * 4 = 156, so total is 3900 + 156 = 4056. That's way more than 1000.So, x = 8 is invalid.Wait, but maybe I should check x = 6 again. Volume is 726, which is less than 1000. So, x = 6 is valid.Wait, but what about x = 5? Even though the width is zero, the volume is zero, which is less than 1000. But since the width is zero, it's not a valid box. So, x must be greater than 5.Wait, but let me check x = 6 again. Volume is 726, which is less than 1000. So, x = 6 is valid.Wait, but what about x = 4? Let me check:x = 4:Volume = (4 + 5)(4 - 5)(4² + 5*4) = (9)(-1)(16 + 20) = 9 * (-1) * 36 = -324Negative volume doesn't make sense, so x = 4 is invalid.Similarly, x = 3:Volume = (3 + 5)(3 - 5)(3² + 5*3) = (8)(-2)(9 + 15) = 8 * (-2) * 24 = -384Negative volume, invalid.x = 2:Volume = (2 + 5)(2 - 5)(2² + 5*2) = (7)(-3)(4 + 10) = 7 * (-3) * 14 = -294Negative volume, invalid.x = 1:Volume = (1 + 5)(1 - 5)(1² + 5*1) = (6)(-4)(1 + 5) = 6 * (-4) * 6 = -144Negative volume, invalid.So, the only positive integer value of x greater than 5 that gives a positive volume less than 1000 is x = 6.Wait, but let me check x = 6 again to be sure.x = 6:Length = 6 + 5 = 11Width = 6 - 5 = 1Height = 6² + 5*6 = 36 + 30 = 66Volume = 11 * 1 * 66 = 726Yes, that's correct. 726 is less than 1000.Now, let me check x = 7 again:Length = 7 + 5 = 12Width = 7 - 5 = 2Height = 7² + 5*7 = 49 + 35 = 84Volume = 12 * 2 * 84 = 20162016 is greater than 1000, so x = 7 is invalid.Wait, but what about x = 6.5? Is that possible? But the problem asks for positive integer values, so x must be an integer. So, x = 6 is the only integer value that works.Wait, but let me check x = 5 again, even though the width is zero. Volume is zero, which is less than 1000, but since the width is zero, it's not a valid box. So, x must be greater than 5.Therefore, the only positive integer value of x that satisfies the condition is x = 6.Wait, but let me check x = 6 again to be absolutely sure.x = 6:Length = 11, width = 1, height = 66Volume = 11 * 1 * 66 = 726 < 1000. Correct.x = 7:Volume = 2016 > 1000. So, invalid.x = 8:Volume = 4056 > 1000. Invalid.x = 9:Volume = (9 + 5)(9 - 5)(9² + 5*9) = 14 * 4 * (81 + 45) = 14 * 4 * 126 = 14 * 504 = 7056 > 1000.So, definitely, x = 6 is the only value.Wait, but let me check x = 5 again, even though the width is zero. Volume is zero, which is less than 1000, but since the width is zero, it's not a valid box. So, x must be greater than 5.Therefore, the number of positive integer values of x is 1.Wait, but just to be thorough, let me check x = 6. Is there any chance that x = 6 might not be valid? Let me recalculate:(6 + 5) = 11(6 - 5) = 1(6² + 5*6) = 36 + 30 = 66Volume = 11 * 1 * 66 = 726. Yes, that's correct.And 726 is less than 1000, so x = 6 is valid.Therefore, the answer is 1.Wait, but just to make sure, let me check x = 6 in the expanded volume equation:V = x⁴ + 5x³ - 25x² - 125xFor x = 6:6⁴ = 12965x³ = 5 * 216 = 1080-25x² = -25 * 36 = -900-125x = -125 * 6 = -750So, V = 1296 + 1080 - 900 - 750 = (1296 + 1080) - (900 + 750) = 2376 - 1650 = 726Yes, that's correct. So, V = 726 < 1000.And for x = 7:7⁴ = 24015x³ = 5 * 343 = 1715-25x² = -25 * 49 = -1225-125x = -125 * 7 = -875So, V = 2401 + 1715 - 1225 - 875 = (2401 + 1715) - (1225 + 875) = 4116 - 2100 = 2016 > 1000So, x = 7 is invalid.Therefore, the only positive integer value of x that satisfies the condition is x = 6.Hence, the number of positive integer values of x is 1.

1993 different equilateral triangles are inscribed in a square (a triangle is inscribed if its three vertices lie on the sides of the square).Prove that there is a point inside the square that lies on the boundary of at least 499 of these triangles.

💡Okay, so I'm trying to solve this problem where there are 1993 different equilateral triangles inscribed in a square. An inscribed triangle means that each of its three vertices lies on the sides of the square. The goal is to prove that there's a point inside the square that lies on the boundary of at least 499 of these triangles.Hmm, let me start by visualizing the square and the triangles. Since all the triangles are equilateral, each has all sides equal and all angles equal to 60 degrees. Now, inscribing such a triangle in a square means that each vertex of the triangle is somewhere on the sides of the square. I remember that in a square, the sides are all equal, and the angles are 90 degrees. So, if I have an equilateral triangle inscribed in the square, the positions of its vertices must be such that they satisfy the 60-degree angles of the triangle while lying on the square's sides.Maybe I should consider the possible positions where the vertices of the triangles can lie on the square. Each side of the square can have multiple vertices from different triangles. Since there are four sides, perhaps the vertices are distributed among these sides.Wait, the problem is about a point inside the square that lies on the boundary of at least 499 triangles. So, this point isn't necessarily a vertex of the triangles but could be somewhere along the edges or inside the square.I think I need to use some combinatorial argument here. Maybe the pigeonhole principle? If there are 1993 triangles, and each triangle has three edges, then there are a total of 1993 * 3 = 5979 edges. These edges are all inside the square, connecting points on the sides.But how does that help me find a point that lies on many of these edges? Maybe I can think about how many times a point can be intersected by these edges.Alternatively, perhaps I should consider the dual problem: instead of looking at the triangles, look at the points where their edges cross. If I can show that some point is crossed by many edges, that would mean it lies on the boundary of many triangles.Wait, but the problem specifies a point inside the square, not necessarily on the boundary. So, maybe I need to consider points inside the square where multiple edges intersect.But I'm not sure if that's the right approach. Let me think differently. Maybe I can fix a point inside the square and count how many triangles have this point on their boundary.But how do I choose such a point? Maybe there's a special point, like the center of the square, that is likely to be on many triangle boundaries.Alternatively, perhaps I can use a grid or some kind of partitioning of the square to argue that some region must contain many triangles, and hence, a point in that region is on many boundaries.Wait, another idea: since all triangles are equilateral, their orientations are constrained. Maybe they all have to be oriented in one of a few specific ways relative to the square.For example, an equilateral triangle inscribed in a square could have one side aligned with a side of the square, or it could be rotated at 30 degrees or something like that.If that's the case, then perhaps the number of possible distinct orientations is limited, and by the pigeonhole principle, many triangles must share the same orientation, leading to overlapping edges and hence a common point.But I'm not sure about the exact number of possible orientations. Maybe it's four, corresponding to the four sides of the square.Wait, actually, for each side of the square, you can inscribe an equilateral triangle with one vertex on that side. So, maybe there are four main orientations, each corresponding to a side.If that's the case, then with 1993 triangles, by the pigeonhole principle, at least one orientation must have at least ceiling(1993 / 4) = 499 triangles.So, if I can show that all these triangles of the same orientation share a common point on their boundaries, then that point would lie on at least 499 triangles.But how do I show that all triangles of the same orientation share a common point?Hmm, maybe if I fix an orientation, say, one vertex on the top side of the square, then the other two vertices must lie on the other sides in a specific way.Wait, let me try to draw this mentally. Suppose I have a square, and I fix one vertex of the triangle on the top side. Then, to form an equilateral triangle, the other two vertices must lie on adjacent sides, say, the right and left sides.But depending on where the first vertex is, the positions of the other two vertices will change. So, maybe all these triangles pass through a common point inside the square.Alternatively, maybe the midpoints of the sides or the center of the square is such a common point.Wait, if I consider the center of the square, maybe many triangles pass through it. But I need to verify if that's the case.Alternatively, maybe each orientation corresponds to a specific point inside the square that all triangles of that orientation pass through.Wait, I think I'm on to something. If I fix an orientation, say, one vertex on the top side, then the other two vertices are determined in a way that they all pass through a specific point inside the square.So, if I have 499 triangles with one vertex on the top side, then all these triangles pass through a specific point inside the square, which would be the required point.Therefore, by the pigeonhole principle, since there are 1993 triangles and four possible orientations, at least one orientation must have at least 499 triangles, and all these triangles pass through a common point inside the square.Hence, that point lies on the boundary of at least 499 triangles.I think that makes sense. So, the key idea is to use the pigeonhole principle based on the possible orientations of the equilateral triangles inscribed in the square, and then argue that all triangles of a given orientation share a common point inside the square.I should probably formalize this a bit more. Let me try to outline the steps:1. Consider the four possible orientations of equilateral triangles inscribed in the square, each corresponding to a side where one vertex lies.2. By the pigeonhole principle, with 1993 triangles and four orientations, at least one orientation must have at least ceiling(1993 / 4) = 499 triangles.3. For each orientation, show that all triangles of that orientation pass through a specific point inside the square.4. Therefore, that specific point lies on the boundary of at least 499 triangles.I think this is a valid approach. The main step is step 3, where I need to show that all triangles of a given orientation pass through a specific point. Maybe this point is the intersection of certain lines or the centroid or something like that.Alternatively, perhaps it's the midpoint of a diagonal or something similar.Wait, let me think about the geometry more carefully. Suppose I fix one vertex of the equilateral triangle on the top side of the square. Then, the other two vertices must lie on the right and left sides.Given that the triangle is equilateral, the positions of these two vertices are determined by the position of the first vertex.But regardless of where the first vertex is, the lines connecting these vertices must intersect at some common point inside the square.Wait, maybe it's the center of the square. Let me check.If I have a square with side length 1, centered at (0.5, 0.5). Suppose I fix a vertex at (x, 1) on the top side. Then, the other two vertices must lie on the right and left sides.To form an equilateral triangle, the distance between (x, 1) and the other two vertices must be equal, and the angles must be 60 degrees.Hmm, this might get complicated, but maybe all these triangles pass through the center point (0.5, 0.5).Alternatively, maybe they pass through another specific point.Wait, perhaps it's better to consider that for each orientation, the triangles are similar and scaled versions, all passing through a common point.So, if I fix the orientation, all triangles of that orientation are similar and share a common point inside the square.Therefore, regardless of the size or position along the side, they all pass through that point.Hence, that point is on the boundary of all these triangles.Therefore, by the pigeonhole principle, since there are 1993 triangles and four orientations, at least one orientation has 499 triangles, all passing through a common point.Thus, that point lies on the boundary of at least 499 triangles.I think this is a solid argument. The key is recognizing that each orientation corresponds to a family of triangles passing through a specific point, and then applying the pigeonhole principle to show that one such family must be large enough.I should probably write this up more formally, but I think the reasoning is sound.

What is the largest multiple of 12 whose negation is greater than -150?

💡To find the largest multiple of 12 whose negation is greater than -150, I start by setting up the inequality:-12x > -150Next, I divide both sides of the inequality by -12, remembering to reverse the inequality sign when dividing by a negative number:x < 150/12Calculating 150 divided by 12 gives approximately 12.5. Since x must be an integer, the largest possible value for x is 12.Finally, I multiply 12 by 12 to find the largest multiple of 12 that satisfies the condition:12 × 12 = 144Therefore, the largest multiple of 12 whose negation is greater than -150 is 144.

Jerry, Gabriel, and Jaxon ask their parents to buy them toys to play with. Jerry is bought 8 more toys than Gabriel, but Gabriel has a certain ratio of toys as Jaxon. Jaxon got 15 toys, and they all have a total of 83 toys. What is the ratio of the number of toys Gabriel has to the number of toys Jaxon has?

💡First, I need to determine the number of toys each child has based on the given information.Let’s denote the number of toys Gabriel has as ( G ) and the number of toys Jerry has as ( J ).1. **Jerry has 8 more toys than Gabriel:** [ J = G + 8 ]2. **Jaxon has 15 toys:** [ text{Jaxon} = 15 ]3. **The total number of toys they all have is 83:** [ G + J + text{Jaxon} = 83 ]Substituting Jaxon's number of toys and the expression for ( J ) in terms of ( G ) into the total equation:[G + (G + 8) + 15 = 83]Combining like terms:[2G + 23 = 83]Subtracting 23 from both sides:[2G = 60]Dividing both sides by 2:[G = 30]Now, we need to find the ratio of the number of toys Gabriel has to the number of toys Jaxon has. Since Gabriel has 30 toys and Jaxon has 15 toys, the ratio is:[G : text{Jaxon} = 30 : 15]To simplify the ratio, we divide both numbers by the greatest common divisor, which is 15:[frac{30}{15} : frac{15}{15} = 2 : 1]Therefore, the ratio of the number of toys Gabriel has to the number of toys Jaxon has is ( 2:1 ).

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