General Thoughts: Mathematics Ext 1 (2 Viewers)

micuzzo

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how did ppl work out the Volume 1... i could not work it out!!!


oh no... dnt tell me it was as simple as [5h^2*root3]/2

plz dnt tell me i just worked it out

EDIT: no thats wrong... phew!
 
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HailSatan

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Was question 2 (a) and 6 (b) (i) as easy as I thought they were?

What did other people get for them?
 

123chryssi123

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I found it pretty hard even Q 4 and 5.
What the hell was the horizontal asymptote?
 

untouchablecuz

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7. b) ii)

did we have to check the nature of the point, becuase seriously

...

i differentiated implicitly and the 2nd derivative/1st derivative (checking each side) was a monster
 

6tgyuio

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you shouldn't need to check its nature, it already gave when it was pos, it was max
 

study-freak

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7. b) ii)

did we have to check the nature of the point, becuase seriously

...

i differentiated implicitly and the 2nd derivative/1st derivative (checking each side) was a monster
Look at the wording of the question
"The maximum value occurs... dtheta/dx=0 and x is positive"
Thus you need to find x satisfying dtheta/dx=0 and x>0
no need to go further
 

untouchablecuz

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oh it did

thanks mate! :D

n2s: read questions more properly next time

...next time
 

elzy93

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Q1-4 were fine, then I pretty much died. The supervisor said she saw my face fall when I started on Q5, haha.
 

AlexJB

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how did ppl work out the Volume 1... i could not work it out!!!


oh no... dnt tell me it was as simple as [5h^2*root3]/2

plz dnt tell me i just worked it out

EDIT: no thats wrong... phew!
You had to find the area of the triangle and then just multiply by 10.

This is what I did: was isoceles. Construct a line through the middle, form 2 equal right angled triangles. We know the height is h, and we know the angles of the triangle. Use trig to find out the length of the base of the triangle. That gives you 2 sides, which you can use to find the area, which you just multiply through by 10.
 

Stephie-Rae

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I was pretty happy with it. Loved Q's 1-4, 5 was good. The bloody binomials in 6 killed me, and i didn't get the last bit of 7 out. I'm just hoping i didn't make too many stupid errors.
 

micuzzo

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You had to find the area of the triangle and then just multiply by 10.

This is what I did: was isoceles. Construct a line through the middle, form 2 equal right angled triangles. We know the height is h, and we know the angles of the triangle. Use trig to find out the length of the base of the triangle. That gives you 2 sides, which you can use to find the area, which you just multiply through by 10.
yer i couldnt find the area... :(

did u keep it as a trig ratio but... coz from wat i remember htere the other sides were unkown
 

shady145

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question 1-5=58/60
q6,7=10/24 ='(
thats wat i think i got
 

ShawnG

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hey guys i got pi/4n for 5a)iv)
dx/dt = nroot(a^2-x^2)
then sin-1 (x/a) = nt
then x= asin(nt)
then particles speed is half maximum speed at (a/root2)
so sub a/root2 in then you get pi/4 = nt no?
 

untouchablecuz

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yer i couldnt find the area... :(

did u keep it as a trig ratio but... coz from wat i remember htere the other sides were unkown
yep

you had one angle 60, the adjacent side h

cos60 = h/hypotenosue

hypotenouse = h/cos60

A = (1/2)(h/cos60)(h/cos60)sin120
 

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