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question:Compute 3 begin{pmatrix} 2 -8 end{pmatrix} - X begin{pmatrix} 1 -7 end{pmatrix}. The answer is -10. What is the value of unknown variable X?
answer:To solve this problem, we need to determine the value of x, which represents the scalar in the second vector. Let's break down the given equation: 3 begin{pmatrix} 2 -8 end{pmatrix} - X begin{pmatrix} 1 -7 end{pmatrix} = begin{pmatrix} -10 -10 end{pmatrix} Expanding the equation, we have: begin{pmatrix} 6 -24 end{pmatrix} - begin{pmatrix} X -7X end{pmatrix} = begin{pmatrix} -10 -10 end{pmatrix} Let's compare the components of the vectors: 6 - X = -10 -24 + 7X = -10 Simplifying the equations, we have: -X = -16 7X = 14 To solve for x, we divide both sides of the equation by -1 in the first equation and by 7 in the second equation: X = 16 X = 2 The value of x is 2. The answer is: 2
question:f there are 6 white daisies, and there are nine times as many pink daisies as white daisies and three less than four times as many red daisies as pink daisies, what is the total number of daisies?
answer:If there are 6 white daisies, and there are nine times as many pink daisies as white daisies, then there are 6 x 9 = 54 pink daisies. If there are three less than four times as many red daisies as pink daisies, then there are (4 x 54) - 3 = 213 red daisies. The total number of daisies is 6 + 54 + 213 = 273 daisies. 273 The answer is: 273
question:f Henry's collection of music CDs consists of 23 country CDs, and he has 3 more country CDs than rock CDs, and twice as many rock CDs as classical CDs, how many classical CDs are there in his collection?
answer:If Henry has 23 country CDs, and he has 3 more country CDs than rock CDs, then he has 23-3= 20 rock CDs. If he has twice as many rock CDs as classical CDs, then he has 20/2= 10 classical CDs. Therefore, Henry has 10 classical CDs in his collection. 10 The answer is: 10
question:Find the length of the parametric curve described by [(x,y) = (2 sin t, 2 cos t)]from t = X to t = pi. If we know the answer to the above question is 2pi, what is the value of unknown variable X?
answer:We want to find the length of the parametric curve described by [(x,y) = (2 sin t, 2 cos t)]from t = X to t = pi. To find the length of the curve, we can use the arc length formula for parametric curves: [L = int_{a}^{b} sqrt{left(frac{dx}{dt}right)^2 + left(frac{dy}{dt}right)^2} dt] In this case, we have: [frac{dx}{dt} = 2 cos t] [frac{dy}{dt} = -2 sin t] Substituting these values into the arc length formula, we have: [L = int_{X}^{pi} sqrt{(2 cos t)^2 + (-2 sin t)^2} dt] Simplifying the expression inside the square root, we get: [L = int_{X}^{pi} sqrt{4 (cos^2 t + sin^2 t)} dt] Since (cos^2 t + sin^2 t = 1), we can simplify further: [L = int_{X}^{pi} sqrt{4} dt] [L = int_{X}^{pi} 2 dt] Evaluating the integral, we have: [L = 2t Big|_{X}^{pi}] [L = 2pi - 2X] Given that the length of the curve is (2pi), we can set up the equation: [2pi = 2pi - 2X] Simplifying, we find: [0 = -2X] Dividing both sides by -2, we get: [X = 0] The value of X is 0. The answer is: 0