Daily Maths Challenges

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submitted 10 months ago* (last edited 9 months ago) by zkfcfbzr to c/dailymaths
 
 
Index of my unnamed series of posted problems
Date Post
2024-05-07 Find a+b
2024-05-09 What is the area of the shaded region?
2024-05-15 Solve for x
2024-05-17 Bounding a function
2024-05-22 Coin-flipping game
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submitted 10 months ago* (last edited 10 months ago) by zkfcfbzr to c/dailymaths
 
 

An 8x5 rectangle. If the bottom left corner is considered (0, 0), then two lines are drawn within the rectangle, from (0, 4) to (8, 1) and from (1, 5) to (7, 0). The smaller two regions of the four these lines cut the rectangle into are shaded. What is their combined area?

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  • Evaluate SUM(1/(n + n^2)) from n = 1 to infty
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submitted 10 months ago* (last edited 10 months ago) by siriusmart to c/dailymaths
 
 
  • Show that arcsin y = arccos x is the equation of a circle.
  • Note that the equation of a circle is x^2+y^2=1.
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Find a+b (self.dailymaths)
submitted 10 months ago* (last edited 10 months ago) by zkfcfbzr to c/dailymaths
 
 

The image is of a large unit square with five smaller disjoint shaded squares contained entirely within it. The five smaller squares are congruent. Four of them are at each corner of the large square. The fifth is in the center, rotated diagonally, so the center of each of its sides is touched by the vertex from one of the other four squares. You are given that the common length for the five smaller congruent squares is (a-sqrt(2)) / b, where a and b are positive integers. What is the value of a + b?

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  • Solve x for x^x*x^x^ = 2
  • Note that the Lambert W function W(x) is the inverse of f(x) = xe^x^
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Prove L'Hopital's rule, nothing fancy.

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Find x for x^x^x^x^x^... = 2

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Prove that the sum of the reciprocals of the Fibonacci numbers up to infinity converges to a finite value.

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submitted 10 months ago* (last edited 10 months ago) by siriusmart to c/dailymaths
 
 

Find ∫e^x sin⁡x dx.

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Siri's Medium (self.dailymaths)
submitted 10 months ago* (last edited 1 month ago) by siriusmart to c/dailymaths
 
 

Index of Siri's Challenges

Date Post Difficulty
2025/01/15 Twice derivative of function 9/10
2025/01/11 Perpendicular of contour lines 8/10
2024/11/06 Derivative with multiple of differential 6/10
2024/08/07 Hypocycloid 7/10
2024/08/04 Extended Euclid's algorithm 6/10
2024/08/01 Multiple of modulus 6/10
2024/06/28 Approximate log base 2 5/10
2024/06/02 Horizontal asymptote of the other kind 7/10
2024/05/25 Angle between two vectors 7/10
2024/05/17 [Unsolved] 1 dimensional gravity 9/10
2024/05/16 Infinite multiplication series 5/10
2024/05/15 Differentiability implies continuity 6/10
2024/05/14 General differential equation 4/10
2024/05/13 Irrational powers 5/10
2024/05/09 Sum of n squares 8/10
2024/05/08 Definition of e^x 5/10
2024/05/07 Evaluate converging sum 5/10
2024/05/06 Equation of circle 4/10
2024/05/05 Fake power tower 7/10
2024/05/04 Prove L'Hopital's rule 6/10
2024/05/03 Infinite exponential 5/10
2024/05/02 Reciprocals of Fibonacci numbers 5/10
2024/05/01 Integral of e^x sinx 5/10
2024/04/29 Approximate 10000 factorial 8/10
2024/04/28 Sum to infinity is -1/12 7/10

If you got any good ideas, PLEASE PM ME I can't come up with that many challenges that quickly.

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  • Estimate 10000!
  • Give our answer in form exp{a ln(a) - b ln(b) + c}
  • Hint: e
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submitted 10 months ago* (last edited 10 months ago) by siriusmart to c/dailymaths
 
 
  • Proof that the infinite sum 1+2+3+4+... = -1/12
  • You may assume that 1-1+1-1+... = 0.5