Chris Harrow

Math teacher interested in creative teaching, problem finding/solving, Computer Algebra Systems, robotics, environment, recreational math

[Chris Harrow @chris_harrow]

@letsgetmathing Yes as one of multiple methods; Ss encouraged to follow what method makes most sense to them, even if different from others. We use systems to find equations for all functions.
After more experience, some turn to @Desmos to efficiently/instantly solve your example.

[Chris Harrow @chris_harrow]

@PuzzleADayBlog 7 or 9: If 7 not 5 & If 9, then also 3 --> not 5
So 5 is excluded --> include 3 & 7

Included 7 --> exclude 9 --> include 11

4 or 6: Either way, 2 is a factor
Already included 3 --> 2 not repeated

Only answer = 2*3*7*11 = 462
2 not repeated --> any extra factors exceeds 1000

[Prof. Feynman @ProfFeynman]

Intelligence isn't the ability to remember and repeat, like they teach you in school. It is the ability to learn from experience, solve problems, and use our knowledge to adapt to new situations.

[Chris Harrow @chris_harrow]

@dbarman You probably already know this, but here's a link to the Which One Doesn't Belong website. Lots of cool puzzles for students.
https://t.co/ElrqGcHpXL

[Chris Harrow @chris_harrow]

@jamestanton googolth root of a googolplex =
= (googolplex)^(1/googol)
= (10 ^ googol)^(1/googol)
= 10^(googol * 1/googol)
= 10

[Chris Harrow @chris_harrow]

@mehrdadbas72335 C with no algebra needed.

Rationale: This is multiple choice, so the correct answer is given. The right side is 8, and a constant is subtracted inside the left side root. Therefore x must be larger than 8 to allow the subtraction to bring the interior down to 8^2.

[chess24 @chess24com]

Shama Yisrael, a 20-year-old from Florida, has crossed the 2200 USCF rating barrier and will become the first female, African-American national master in the country's history when the rating lists are updated in August.
https://t.co/jt0hTIsihx

[Chris Harrow @chris_harrow]

@graf_paper Delightful problems! Thanks for sharing. Did not expect Fibonacci at outset, so even more fun!
Lovely extension, @Rush_MathsKS5 .

[Dave Richeson @divbyzero]

A mathematician watching the summer Olympics: "Why aren't both of these events called the 'parallel bars'?"

[Chris Harrow @chris_harrow]

@alexanderdrspan @mehrdadbas72335 Three answers for a,b,c in N.
Three more answers for a,b,c in Q.
Infinite solutions for a,b,c in R.

[Tim Brzezinski @TimBrzezinski]

Physical example that clearly illustrates why 2^0 = 1. #math #CAMT24

[Chris Harrow @chris_harrow]

@icecolbeveridge @Daily_Epsilon @capobianco_slv Yes. I don't know its proper name, but if prime factorization of some number is p1^n1*p2^n2*...*pk^nk where p1...pk are the number's k prime factors and n1...nk are respective frequencies, then number has (n1+1)*(n2+1)*...*(nk+1) factors. Since 5 is prime, p^4 is only option.

[Cliff Pickover @pickover]

Mathematics.

A shocking formula to calculate any digit of Pi without having to know any preceding digits. More info: https://t.co/bcZ7h9qkfx

[Chris Harrow @chris_harrow]

@ybgoi Triangles have same height, so a ratio of their areas is equal to a ratio of their bases:
A1/A2 = (0.5*b1*h)/(0.5*b2*h) = b1/b2

[Chris Harrow @chris_harrow]

@PuzzleADayBlog By initially matching each new condition with those who missed at least one prior, a minimum 10% remain with all 4 conditions. Image outlines my reasoning.
NOTE: Adding one more malady with frequency 90% would make it possible that 0% endure all five conditions.

[Chris Harrow @chris_harrow]

@Daily_Epsilon Perfect squares are the only numbers with an odd number of factors. That quickly narrows the list of possibilities...

Because 5 is prime, you're looking for a perfect square whose prime factorization is n^4. That leaves one solution...

[Chris Harrow @chris_harrow]

@PuzzleADayBlog As @hugh_bothwell noted, a + 4b + 6c + 4d + e = 45, so a & e and b & d are interchangeable. I ran Python code to scan for solutions. If different arrangements of the bottom row are considered distinct, there are 60 solutions with low sum in 2nd row ranging 17...22.

[Cliff Pickover @pickover]

Mathematics, statistics, graphs, best fit.

By @ErrantScience, https://t.co/xXGiplorRH, cc-by-nc