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leesh95

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Can someone plz do the sine rule question! Q14c I think? Wts sinx?:$
That question was actually really easy but I got it completely wrong in the exam.:cry:
I think the answer was sinx= 7sin120/13
God I hope I pass.
 

suvmong

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The trapezoidal rule uses trapezoidal shapes which would form straight lines across the tops of the tent. Since its concaved in, Simpsons rule would not work as well because it uses PARABOLAS and therefor concaves out to find the area, allowing for a wider margin of error
 

aDimitri

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That question was actually really easy but I got it completely wrong in the exam.:cry:
I think the answer was sinx= 7sin120/13
God I hope I pass.
this is correct, except sin120 = sqrt(3)/2 so you can simplify it to what i said in my previous post. 7sqrt(3)/26
 

hjed

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this is correct, except sin120 = sqrt(3)/2 so you can simplify it to what i said in my previous post. 7sqrt(3)/26
Except that's what sinx equalled, not what x equalled. It was sinx=7sqrt(3)/26 or x=sinh( 7 sqrt(3)/26 )

Did anyone manage to get it simpler than that?
 

aDimitri

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Except that's what sinx equalled, not what x equalled. It was sinx=7sqrt(3)/26 or x=sinh( 7 sqrt(3)/26 )

Did anyone manage to get it simpler than that?
no, it was sinx = 7sqrt(3)/26. the question explicitly stated find the exact value of sinx. that is as simple as it goes.
 

andybandy

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omfg i just realised i done a stupid mistake and use sin isntead of tan to find the bottom length, i made so many stupid mistakes and forgot to leave it in exact form
 

leesh95

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omfg i just realised i done a stupid mistake and use sin isntead of tan to find the bottom length, i made so many stupid mistakes and forgot to leave it in exact form
OMG same I used the cos rule to find it and only realized at the last moment what I'd done.

FML
 

andybandy

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OMG same I used the cos rule to find it and only realized at the last moment what I'd done.

FML
i cant believe i made that many silly mistakes, really need a band 6 or my atar wont even make it above 80 , its asif i wasnt thinking throughout the exam
 

bedpotato

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i cant believe i made that many silly mistakes, really need a band 6 or my atar wont even make it above 80 , its asif i wasnt thinking throughout the exam
everything you just said sums up exactly how i feel right now

but, don't dwell on it, focus on your other subjects now :)
 

lolwot

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my marks best case scenario (marks for significant working)

mc = 10
sect 11 = 14
sect 12 = 13
sect 13 = 13
sect 14 = 9
sect 15 = 11
sect 16 = 7

77

hope atleast >70

ah its out of my hands now! good luck everyone!
 

nboscheinen

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Ride on i feel like I got that, except just took one more step to make it x = sin^-1...

And I found the exam to be the most difficult out of the all the past papers. The format through me off more so than anything. I'm used to having the questions gradually get harder as you go, not a difficult one or two thrown in each question.

Btw for 16. i. did anyone make both of the gradients equal to find x? Like the dy/dx = 5

ie. 4x-3=5

 

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