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237643 Questions
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2. If |πβ© = |π1β© + |π2β© and |πβ© = |π1β© β |π2β© , Show that β¨π|πβ© + β¨π|πβ© = 2β¨π1|π1β© + 2β¨π2|π2β©
2. If |πβ© = |π1β© + |π2β© and |πβ© = |π1β© β |π2β© , Show that β¨π|πβ© + β¨π|πβ© = 2β¨π1|π1β© + 2β¨π2|π2β©
Guest
Jan 12, 2023
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211
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Distributions
(a) In how many ways can you distribute 4 distinguishable balls among 3 indistinguishable boxes?
(b) In how many ways can you distribute 4 indistinguishable balls among 5 distinguishable boxes?
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Guest
Jan 12, 2023
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195
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Binomial Theorem
(a) Simplify (n/k)/(n/(k - 1))
(b) For some positive integer n, the expansion of (1 + x)^n has three consecutive coefficients a, b, c that satisfy 1:8:28. What must n be?
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Guest
Jan 12, 2023
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204
1
Counting
Find the number of positive integers that satisfy the following conditions:
* Each digit is a 1 or a 2 or a 3
* The sum of the digits is 10
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Guest
Jan 12, 2023
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169
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Probability
A bag contains five white balls and three black balls. Your goal is to draw two white balls.
(a) You simultaneously draw two balls at random. What is the probability that they are both white?
(b) You simultaneously draw two balls
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Guest
Jan 12, 2023
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199
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help math
Let n be a positive integer. Let k be a positive integer.
(a) Using a counting argument, show that C(n - 1, k - 1) + C(n - 1, k) = C(n,k).
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Guest
Jan 12, 2023
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158
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Expected value
The grid below is made up of line segments, like the line segment in red.
There are a number of paths that go from A to B in the grid, where every step goes to the right or up. If we choose a line segment at random, then
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Guest
Jan 12, 2023
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194
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Function
The function f(n) satisfies
binom(2n)n - binom(2n + 1)(2n) = f(n) *binom(2n + 1)(n + 1)
for all positive integers n. Find f(n).
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Guest
Jan 12, 2023
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176
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Counting arrangements
Find the number of ways of arranging the numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 in a row so that the product of any two adjacent numbers is even or a mutliple of 3
Guest
Jan 12, 2023
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181
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Absolute value
Find all solutions of the equation
|x^2 - 30x - 1| + |x^2 - 30x + 29| = 30.
Guest
Jan 12, 2023
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167
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Angle bisectors
Let ABC be a triangle, and let its angle bisectors be AD, BE, and CF, which intersect at I. If DI = 3, BD = 4, and BI = 8, then find the area of triangle ABC.
Guest
Jan 12, 2023
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168
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help counting
In how many ways can the numbers 1 through 5 be entered once each into the five boxes below so that all the given inequalities are true?
Guest
Jan 12, 2023
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155
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plz help
A stick is broken at two points, at random. If the length of the stick is 6, then what is the probability that all three resulting pieces are shorter than 3 units?
Guest
Jan 12, 2023
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164
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βwas ist rad
was ist rad
Guest
Jan 12, 2023
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160
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Geometry
In triangle PQR, M is the midpoint of PQ. Let X be the point on QR such that PX bisects angle QPR, and let the perpendicular bisector of PQ intersect AX at Y. If PQ = 36, PR = 22, QR = 26, and MY = 8, then find the area
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Guest
Jan 12, 2023
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