Recent content by physion
-
Challenge Math Challenge - May 2020
Apologies, doesn't my line of reasoning rule out all k > 3, not everything except it? Also, my argument should indeed instead specify x 'more than or equal' to 0 and 'non-negative' instead of 'positive', but the line of reasoning should still hold.- physion
- Post #18
- Forum: Math Proof Training and Practice
-
Challenge Math Challenge - May 2020
Ah, thanks! My reasoning didn't really make much sense looking back on it now. Let's say that, for negative k, we use ##k = -n## where n > 0, so we have ##(x-n)^3 = x^3 + 8x^2 - 6x + 8## Importantly, ##8x^2 - 6x + 8 > 0## for all positive x. However, upon expanding, and canceling x^3 on both...- physion
- Post #16
- Forum: Math Proof Training and Practice
-
Challenge Math Challenge - May 2020
As shown above, ##x^3 < y^3## (i.e. the case where k = 0) --> ##x < y## , and thus ##k > 0## Similarly, ##y^3 < (x+3)^3## --> ##y < x + 3## We are left with ##k = 1, k = 2.##- physion
- Post #13
- Forum: Math Proof Training and Practice
-
How Can Self-Taught Physics and Math Spark Excitement in 9th Graders?
Hi everyone! I'm in 9th grade and I've been teaching myself (albeit haphazardly) physics and maths for a while now in order to escape the boredom of the classroom, but I thought it might be a good idea to seek some input now and then. :) I look forward to making some mistakes--just hopefully...- physion
- Thread
- Replies: 1
- Forum: New Member Introductions