Activity for Este
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #289496 |
History hidden: Detailed history before this event is hidden because of a redaction. |
— | 9 months ago |
| Edit | Post #289496 |
Post edited: |
— | 9 months ago |
| Edit | Post #289496 |
Post edited: |
— | 9 months ago |
| Edit | Post #289496 |
Post edited: |
— | 9 months ago |
| Edit | Post #289496 |
Post edited: |
— | 9 months ago |
| Edit | Post #289496 | Initial revision | — | 9 months ago |
| Question | — |
1 picture proof for the triangle inequality and the reverse triangle inequality Michael Spivak's Calculus (2008 4 edn), Exercise 12, p 16. (vi) is the Reverse Triangle Inequality. >(iv) $|x-y| ≤ |x| + |y|$. (Give a very short proof.) (v) $\color{limegreen}{|x|-|y|} ≤ |x-y|$. (A very short proof is possible, if you write things in the right way). (vi) ${\color{m... (more) |
— | 9 months ago |
| Edit | Post #289495 | Initial revision | — | 9 months ago |
| Question | — |
Picture proof for expansion of $x^n−y^n$ Most students fail to intuit $x^n−y^n \equiv (x−y)(x^{n−1}+x^{n−2}y+...+xy^{n−2}+y^{n−1})$ as substantiated by the glut of duplicates, at least 20 on Math StackExchange. Thus how can students pictorialize it? I seek solely VISUAL (not algebraic) proofs here. After substituting $z = \dfrac xy... (more) |
— | 9 months ago |