Trigonometry question (1 Viewer)

[nazfiz]

This question has got me stumped. Any help would be appreciated.
Thanks.

 

[SpiralFlex]

Always draw a pretty diagram.



Since the ladder is a constant (It cannot distort itself, unless we are in Harry Potter!) let this be .


We will note:



Now,



and




Eliminating




Our relationship is now recognised. The one we established before,




Solve for

We should get,




Now we can easily find

We can see that,



So we must form a relationship between them.


In triangle AB'C and ABC respectively,











As we said before,

 

[RivalryofTroll]

Use the power of sine rule!

Always draw yourself a pretty diagram, here I introduced D.

Not bad. ><

 

[SpiralFlex]

Not bad. ><

Fine, I will draw a better one if this does not satisfy you!

 

[nazfiz]

Always draw a pretty diagram.



Since the ladder is a constant (It cannot distort itself, unless we are in Harry Potter!) let this be .


We will note:



Now,



and





Eliminating




Our relationship is now recognised. The one we established before,




Solve for

Thanks Spiral. But shouldn't it be cos70/cos55=AC/A'C

 

[SpiralFlex]

Oops it's 55 not 50. Sorry! Figures should be correct.

 

[nazfiz]

No Worries. Thanks for the Help!

 

[Bored_of_HSC]

With most trig problems most of it is just finding a common variable. The rest is usually alright.

 

[SpiralFlex]

In this case, the examiner deliberately tried to confuse you. You need to recognise that a ladder length will always be a constant.

 

[Carrotsticks]

In this case, the examiner deliberately tried to confuse you. You need to recognise that a ladder length will always be a constant.

You can easily tell the rote learners from the people who really understand the situation.

If in real life, anybody will know that the length of the ladder does not change (assuming it's not collapsible lol).

However if put into a problem, many people do not recognise this.

 

[SpiralFlex]

You can easily tell the rote learners from the people who really understand the situation.

If in real life, anybody will know that the length of the ladder does not change (assuming it's not collapsible lol).

However if put into a problem, many people do not recognise this.

This question would be much clearer if they stated, "In a non-magical world", because I have seen films where ladders do change in length.

 

[Bored_of_HSC]

You can easily tell the rote learners from the people who really understand the situation.

If in real life, anybody will know that the length of the ladder does not change (assuming it's not collapsible lol).

However if put into a problem, many people do not recognise this.

That's the pure essence of problem solving. (being capable in applying theory into practice)

 

[RivalryofTroll]

Fine, I will draw a better one if this does not satisfy you!

(Not bad = Pretty Good) in my dictionary. Also, I was talking about the way/steps to do it rather than the actual diagram.