how to approach the "show that" questions (1 Viewer)

iamdumdum

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I ENCOUNTERED A QUESTION, I COULDNT ANSWER AND I WAS LIKE ARHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH, WHY CAN I NOT ANSWER THIS.

its a "show that" question and im wondering how would someone approach these questions?
 

RishBonjour

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there are a few types from what i remember e.g. "show LHS = RHS" or show that "area/volume = ..."
giving an example of the question would help.
 

Shadowdude

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I take "Show" questions to be like "Prove" questions.

Not sure if that helps - but that's how I approach them.
 

zhiying

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Start LHS, keep 1 eye on RHS, look at what you need and what you already have.

Then maths.
 

RishBonjour

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Start LHS, keep 1 eye on RHS, look at what you need and what you already have.

Then maths.
but some have diagrams e.g. "show the area/volume is ="
they generally pop up in last questions

there are multiple ways to approach them, some are as easy as breaking the areas down and adding them together lol.
 

SpiralFlex

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Not always should you start with LHS, we shouldn't be tied down with this. There are different ways you can start. Can you think of some different ones? Here are some

[1] Instead ask yourself can you somehow manipulate or rearrange the equation so we're proving the same thing in a different form,

Eg.

It is not obvious to us what we are need to do if you haven't seen this. However, notice that we can rearrange the question, we aim to prove this instead



Factorising LHS



By the trivial inequality, squaring a real number must be greater or equal to 0.


[2] Another way we can do this is think of a clever substitution to use.


[3] Using other results and identities





Adding these will yield the result.


It is good to experiment and investigate instead of starting with the generic LHS equals
 

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