Edexcel IGCSE Maths 复习笔记 2.8.1 Proof/Reasoning - Algebraic
What is proof?
- Proof is the process of showing something is true in every case, often by using algebra
Given an algebraic expression…
- Expand brackets
- Simplify (work with left-hand side only if = sign involved)
- Make sure you finish with the statement you are proving
Given just words…
- This is a bit trickier but turning it into algebra is usually the best thing to do
4. Give things names (use as few letters as possible):
-
- n is “any integer” (or m or k or…)
- n + 1 is the integer after n (“consecutive”)
- 2n is an even integer (2n + 2 is the next one)
- 2m is a different even integer
- 2n + 1 is an odd integer (and 2n + 3 is the next one)
5. Then go on as above (“Given an Algebraic Expression”)
Exam Tip
“A multiple of k” means it can be written as k(……) – ie. k × …
Worked Example
转载自savemyexam