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question:The sum of two numbers is 15, and their product is 36. What is the smaller number?

answer:Let x be one number, and y be the other number. We have: 1. x + y = 15 2. xy = 36 To solve for x and y, we can use the quadratic formula based on the idea that these are roots of the quadratic equation: [ t^2 - (x+y)t + xy = 0 ] Substituting the given information: [ t^2 - 15t + 36 = 0 ] Using the quadratic formula: [ t = frac{-b pm sqrt{b^2 - 4ac}}{2a} = frac{-(-15) pm sqrt{(-15)^2 - 4 times 1 times 36}}{2 times 1} ] [ t = frac{15 pm sqrt{225 - 144}}{2} ] [ t = frac{15 pm sqrt{81}}{2} ] [ t = frac{15 pm 9}{2} ] This gives us: [ t_1 = frac{15 + 9}{2} = 12 ] [ t_2 = frac{15 - 9}{2} = 3 ] Since we are asked for the smaller number, boxed{3} is the smaller number.

question:Given the function f(x)=(log_2x)^2log_2x^2+3, when xin[1,4], the maximum value of f(x) is m, and the minimum value is n. (1) If the terminal side of angle alpha passes through point p(m,n), find the value of sin alpha+cos alpha; (2) Let g(x)=mcos (nx+ frac{pi}{m})n, h(x)=g(x)k has two different zeros x_1,x_2 in [0, frac{pi}{2}], find the range of k.

answer:Solution: (1)f(x)=(log_2x)^2-log_2x^2+3, Let log_2x=t, therefore g(t)=t^2-2t+3, tin[0,2] The maximum value m=3, the minimum value n=2, therefore P(3,2), therefore sin alpha= frac {2}{ sqrt {13}}, cos alpha= frac {3}{ sqrt {13}}, therefore sin alpha+cos alpha= frac {5}{ sqrt {13}}. (2)g(x)=3cos (2x+ frac {pi}{3})-2, h(x)=g(x)-k=3cos (2x+ frac {pi}{3})-2-k Rightarrow 3cos (2x+ frac {pi}{3})=2+k, When xin[0, frac {pi}{2}], 2x+ frac {pi}{3}in[ frac {pi}{3}, frac {4pi}{3}], therefore h(x)=g(x)-k has two different zeros x_1, x_2 Leftrightarrow y=3cos x, xin[0, frac{4pi}{3}] intersects with y=2+k at two points, therefore k+2in(-3,- frac {3}{2}], therefore kin(-5,- frac{7}{2}]. Thus, the answers are boxed{frac {5}{ sqrt {13}}} for part (1) and boxed{(-5,- frac{7}{2}]} for part (2).

question:A triangle has vertices (0,0), (1,1), and (6m,0), and the line y = mx divides the triangle into two triangles of equal area. What is the sum of all possible values of m? textbf{A} !frac {1}{3} qquad textbf{(B)} !frac {1}{6} qquad textbf{(C)} frac {1}{6} qquad textbf{(D)} frac {1}{3} qquad textbf{(E)} frac {1}{2}

answer:1. **Identify the vertices and the line dividing the triangle**: Let's label the vertices of the triangle as A = (0,0), B = (1,1), and C = (6m,0). The line y = mx is supposed to divide the triangle into two triangles of equal area. 2. **Determine the intersection point**: The line y = mx will intersect the line segment BC. Let D be the point of intersection. The coordinates of D can be found by setting the y-coordinates of the line y = mx and the line segment BC equal. The line segment BC can be represented by the equation y = -frac{1}{6m-1}(x-1) (using point-slope form and the points B and C). Setting mx = -frac{1}{6m-1}(x-1) and solving for x, we find the x-coordinate of D. 3. **Condition for equal areas**: The triangles ABD and ACD will have equal areas if D is the midpoint of BC. The midpoint of BC is given by left(frac{6m+1}{2}, frac{1}{2}right). For D to be on the line y = mx, the coordinates must satisfy y = mx. Substituting the midpoint coordinates into the line equation, we get: [ frac{1}{2} = m cdot frac{6m+1}{2} ] Simplifying this equation: [ 1 = m(6m+1) implies 6m^2 + m - 1 = 0 ] 4. **Solve the quadratic equation**: The quadratic equation 6m^2 + m - 1 = 0 can be solved using the quadratic formula: [ m = frac{-b pm sqrt{b^2 - 4ac}}{2a} quad text{where } a = 6, b = 1, c = -1 ] [ m = frac{-1 pm sqrt{1 + 24}}{12} = frac{-1 pm 5}{12} ] [ m = frac{4}{12} = frac{1}{3}, quad m = frac{-6}{12} = -frac{1}{2} ] 5. **Sum of all possible values of m**: Using Vieta's formulas, the sum of the roots of the equation 6m^2 + m - 1 = 0 is given by -frac{b}{a} = -frac{1}{6}. Thus, the sum of all possible values of m is boxed{textbf{(B)} - !frac {1}{6}}.

question:The light glows for some seconds. It glowed 292.29411764705884 times between 1:57:58 and 3:20:47 am. How many seconds does the light glow for?

answer:To find out how many seconds the light glows for, we need to calculate the total time between 1:57:58 am and 3:20:47 am and then divide that by the number of times the light glowed. First, let's find the total time in seconds between the two timestamps: From 1:57:58 to 2:00:00 is 2 minutes and 2 seconds. From 2:00:00 to 3:00:00 is 1 hour, which is 60 minutes or 3600 seconds. From 3:00:00 to 3:20:47 is 20 minutes and 47 seconds. Now, let's convert the minutes to seconds and add all the seconds together: 2 minutes = 2 * 60 = 120 seconds 120 seconds (from 1:57:58 to 2:00:00) + 2 seconds = 122 seconds 3600 seconds (from 2:00:00 to 3:00:00) 20 minutes = 20 * 60 = 1200 seconds 1200 seconds + 47 seconds (from 3:00:00 to 3:20:47) = 1247 seconds Now, let's add all the seconds together: 122 seconds + 3600 seconds + 1247 seconds = 4969 seconds This is the total time in seconds between 1:57:58 am and 3:20:47 am. Now, let's divide this total time by the number of times the light glowed: 4969 seconds / 292.29411764705884 times = 17 seconds (rounded to the nearest whole number) So, the light glows for approximately boxed{17} seconds each time.

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