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Renumi
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#1
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My maths exam is tomorrow and I'm doing some last minute revision but I can't do this question? I've looked online but found nothing
Any help would be loved!
(If it helps, it is a practice question on the exact values of Trig)

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Last edited by Renumi; 4 weeks ago
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Sonicalireza
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is there any other information given about the triangle?
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haxhacks
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There must have been information given in part a, probably about an angle. It's impossible to do with the screenshot you've given
(Original post by Renumi)
My maths exam is tomorrow and I'm doing some last minute revision but I can't do this question? I've looked online but found nothing
Any help would be loved!
(If it helps, it is a practice question on the exact values of Trig)

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Renumi
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(Original post by Sonicalireza)
is there any other information given about the triangle?
Ah, yes, sorry! Only just realized that it's a part of another question, still don't understand it though.
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Basically, the angles are 90, 30, and 60, though I don't know which angle is which
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Spookyayu
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The angle opposite the hypotenuse is the right angle and the angle on the "base" is 30 degrees.Name:  15583898362621834495411.jpg
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(Original post by Renumi)
Ah, yes, sorry! Only just realized that it's a part of another question, still don't understand it though.
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Basically, the angles are 90, 30, and 60, though I don't know which angle is which
You can use the sine rule from here, I think.
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haxhacks
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You can work out the other two angles by doing 1 x 30 and 2 x 30. The angle of 60 will have an opposite which is the smallest side. You've got to visualise this. Try drawing a sketch of a right angles triangle with angles 30 and 60. You'll figure out which one is the smaller side. Using sin60=o/h and rearrange for O
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haxhacks
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Or that, there are multiple different methods
(Original post by Spookyayu)
The angle opposite the hypotenuse is the right angle and the angle on the "base" is 30 degrees.Name:  15583898362621834495411.jpg
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You can use the sine rule from here, I think.
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Renumi
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(Original post by haxhacks)
You can work out the other two angles by doing 1 x 30 and 2 x 30. The angle of 60 will have an opposite which is the smallest side. You've got to visualise this. Try drawing a sketch of a right angles triangle with angles 30 and 60. You'll figure out which one is the smaller side. Using sin60=o/h and rearrange for O
Thank you both for the help! I decided to use this method and got 16.9893 which apparently is wrong
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ElbertAinstein
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Your x is going to be the longest side, try calculating the other side
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Spookyayu
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The question asks you to find the shortest line, right?
(Original post by Renumi)
Thank you both for the help! I decided to use this method and got 16.9893 which apparently is wrong
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The line opposite 30 degrees is the shortest side. Think about it like this, if a door is opened very slightly, the small angle means that the "open" space to pass through is very tight. Open the door more, the angle gets bigger and you have more space to walk through the door. The shortest line in a right angled triangle will always be opposite the smallest angle for this reason
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Renumi
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(Original post by Renumi)
Thank you both for the help! I decided to use this method and got 16.9893 which apparently is wrong
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Nevermind, I got it! It turns out it was cos(60)=X/21
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Renumi
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(Original post by Spookyayu)
The question asks you to find the shortest line, right?

The line opposite 30 degrees is the shortest side. Think about it like this, if a door is opened very slightly, the small angle means that the "open" space to pass through is very tight. Open the door more, the angle gets bigger and you have more space to walk through the door. The shortest line in a right angled triangle will always be opposite the smallest angle for this reason
Thank you! This explanation helped me get it!
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haxhacks
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Yeah my bad it was cos.
(Original post by Renumi)
Thank you both for the help! I decided to use this method and got 16.9893 which apparently is wrong
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