APM - Q2 - Finding a general result

2021-10-25
1 min read

Flashcards

2021-10-25

$$\frac{1 + 4}{2} = \frac{1 + 2 + 3 + 4}{4}$$ What general rule is this??

That the average of two numbers is also the average of the sum between them.

$$\frac{b^2 + b - a^2 + a}{b - a + 1}$$ What is the trick to simplifying this??

Realising that it’s factorising but one bracket has three terms.

$$ \frac{(b - a + 1)(a + b)}{b -a + 1} $$

What’s a trick for coming up with a formula for the sum of $k\text{th}$ powers over the integers??

Assuming that it will be equal a $(k + 1)$ degree polynomial and coming up with 5 equations.


Metadata
date: 2021-10-25 19:07
summary: how can we work out a formula for the sum of cubes?
tags:
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- '@?advanced-problems-in-mathematics'
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- '@?maths'
title: APM - Q2 - Finding a general result