# MAT - Paper 2015 - Q2

> Source: https://ollybritton.com/notes/maths/problems/mat/2015/q1c/ · Updated: 2021-10-10 · Tags: mat, notes, maths

## Flashcards
### 2021-10-10
##### If you want to prove an expression can't be a cube, how could you do it??
Show that it can't lie between two consecutive cubes.

##### Why can't $k^3 + 2k^2 + 2k + 1$ be a cube if $k^3 < k^3 + 2k^2 + 2k + 1 < (k + 1)^3$??
Because you can't have an cube number between two consecutive cube numbers.

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