Monthly Archives: January 2026

IB HL Probability 4 sided dice expectation winnings in euro

Posted on January 21, 2026 by Sumant Sumant
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IB HL probability and expectation

Posted on January 21, 2026 by Sumant Sumant
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AP Calculus Absolute limit that doesn’t exist

Posted on January 20, 2026 by Sumant Sumant

Determine

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AP Calculus Evaluating a cube root limit in three different ways

Posted on January 20, 2026 by Sumant Sumant

Determine the limit

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Fermat Contest 2020 Question 23 on Functional Equation

Posted on January 20, 2026 by Sumant Sumant

There are real numbers and for which the function has the properties that for all real numbers and for all real numbers . What is the value of

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Particular solution to variable separable equation

Posted on January 19, 2026 by Sumant Sumant

When my student asked it. I was stumped. The way to think it as y = f(x) and y’= dy/dx Continue reading →

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IB HL Cubic Equation with Purely Imaginary Roots

Posted on January 18, 2026 by Sumant Sumant

Consider the family of polynomials of the form where coefficients and belong to the set .

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IB HL Combinatorics (Arranging four letters and 10 digits)

Posted on January 18, 2026 by Sumant Sumant

The barcode strings of a new product are created from four letters A,B,C,D and ten digits 0,1,2,..,9. No three of the letters may be written consecutively in a barcode string. There is no restriction on the order in which the … Continue reading →

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Fermat Contest 2019 Question 20 on and equilateral triangle on a circle with a radius 2

Posted on January 18, 2026 by Sumant Sumant

The vertices of an equilateral triangle lie on a circle with radius 2. What is the area of the triangle ?

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Fermat Contest 2019 Question 19 on Functional Equation

Posted on January 18, 2026 by Sumant Sumant

The function has the properties that and for every integer . What is the value of ?

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