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# A trigonometry problem :S Tweet

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1. A trigonometry problem :S
a ladder 2.5m long leans against a vertical wall so that it makes an angle of 68(degrees) with the horizontal grounf. how far up the wall does the aldder reach ? give your answer to one decimal place.

^^ i have worked it out however im not fully convinced that my answer is correct as it looks odd. my answer was 0.9m by using cos
thankyou for any help.
2. Re: A trigonometry problem :S
It might be easier just to post your entire homework in one thread
3. Re: A trigonometry problem :S
BTW your answer is wrong since the wall is OPPOSITE your angle
4. Re: A trigonometry problem :S
(Original post by silverose)
a ladder 2.5m long leans against a vertical wall so that it makes an angle of 68(degrees) with the horizontal grounf. how far up the wall does the aldder reach ? give your answer to one decimal place.

^^ i have worked it out however im not fully convinced that my answer is correct as it looks odd. my answer was 0.9m by using cos
thankyou for any help.
You have found the distance from the wall to the foot of the ladder.

You need sin and not cos.
5. Re: A trigonometry problem :S
sin x = opposite/hypotenuse
sin68= length/2.5

length=2.5sin68= 2.3m (2sf)
6. Re: A trigonometry problem :S
(Original post by silverose)
a ladder 2.5m long leans against a vertical wall so that it makes an angle of 68(degrees) with the horizontal grounf. how far up the wall does the aldder reach ? give your answer to one decimal place.

^^ i have worked it out however im not fully convinced that my answer is correct as it looks odd. my answer was 0.9m by using cos
thankyou for any help.
See the diagram below:

7. Re: A trigonometry problem :S
.....
Last edited by MarshmallowBob; 06-04-2012 at 15:00. Reason: Double posted
8. Re: A trigonometry problem :S
#.\
#...\
#.....\
#.......\ 2.5m.......sin68= x/2.5
#.........\ ............x= 2.5Xsin68
#...........\...........x=2.3 m (1.dp)
#_____(68 \
Last edited by MarshmallowBob; 06-04-2012 at 15:01.
9. Re: A trigonometry problem :S
(Original post by MarshmallowBob)
#.\
#...\
#.....\
#.......\ 2.5m.......sin68= x/2.5
#.........\ ............x= 2.5Xsin68
#...........\...........x=2.3 m (1.dp)
#_____(68 \
I think i posted a better diagram above .
10. Re: A trigonometry problem :S
(Original post by raheem94)
See the diagram below:

This picture made my day.
11. Re: A trigonometry problem :S
(Original post by raheem94)
I think i posted a better diagram above .
Lol i couldnt agree more :P i had wasted a good 5 mins with the diagram, then is saw your post, so i thought might aswell post it.
12. Re: A trigonometry problem :S
(Original post by myfriendSQRT(-1))
This picture made my day.
Lol
13. Re: A trigonometry problem :S
(Original post by raheem94)
Lol
I particularly enjoyed that you clarified where the wall was.
14. Re: A trigonometry problem :S
(Original post by Hype en Ecosse)
I particularly enjoyed that you clarified where the wall was.
How do you enjoy a maths diagram?
15. Re: A trigonometry problem :S
(Original post by raheem94)
How do you enjoy a maths diagram?
The same way you enjoy anything? The notion that you had to clarify that the only vertical structure in the diagram was a wall made me smile.
16. Re: A trigonometry problem :S
(Original post by Hype en Ecosse)
The same way you enjoy anything? The notion that you had to clarify that the only vertical structure in the diagram was a wall made me smile.
I just wanted to label the diagram. However, i didn't labelled the horizontal ground .
17. Re: A trigonometry problem :S
(Original post by TenOfThem)
It might be easier just to post your entire homework in one thread
nobody's forcing you to help me .. don't like the fact that i can't do all my homework by myself but i'm trying to get help then keep scrolling and keep any nasty comments to yourself love.
18. Re: A trigonometry problem :S
Thankyou so much for the patience with the diagrams guys .. really helped
19. Re: A trigonometry problem :S
(Original post by silverose)
nobody's forcing you to help me .. don't like the fact that i can't do all my homework by myself but i'm trying to get help then keep scrolling and keep any nasty comments to yourself love.
Its not a 'nasty comment'. Why can't you post all the questions in one thread?

We don't have problem with you not able to do your homework, but you were suggested to post all the questions in one thread rather than making multiple threads.
20. Re: A trigonometry problem :S
(Original post by silverose)
nobody's forcing you to help me .. don't like the fact that i can't do all my homework by myself but i'm trying to get help then keep scrolling and keep any nasty comments to yourself love.
Accidentally neg repped you when I wanted to pos rep you! Sorry