CSSA Trials: 3U Maths thoughts (1 Viewer)

TrentsUnicorn

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i found it an overall pretty good exam, could one of u guys let us know how u went on that question with the rate of change with the weather balloon :)
With the rate of change of the angle? Lol I did it, don't know how right it was though.... Got some fraction, don't remember exactly though :/ think I got 1/40? But don't remember
 

km1307

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What did your graph for the inverse trig question look like?
 

Thank_You

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Fuck me sideways, skipped easy shit like:

cos(theta) = 1/5. Find tan(theta/2).

Now I know how to do it.

Couldn't see the circle geometry question, wasted 15mins on it.

Now I know how to do it.

Couldn't see the pattern in the mathematical induction question.

Now I know how to do it.

Got the equation wrong for the graph, which the answer was actually: 1/2[(x-2)^2(x+1)]

That last projectile question was fairly easy, but when solving via sum and product of roots, accidentally left out an 'R'. Fuckkkkkk,

There goes at least 7-10 marks
Yeah, that answer is right




What did your graph for the inverse trig question look like?
You just draw the left side the graph and reflect it about y=x

was actually probably easier than past CSSA papers by quite a significant amount.
Agreed, yet still I screwed up

With the rate of change of the angle? Lol I did it, don't know how right it was though.... Got some fraction, don't remember exactly though :/ think I got 1/40? But don't remember
Yeah I got that!!
 
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photastic

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How do you know the answer for the polynomial already?
 
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How did you guys do

cos(theta) = 1/5. Find tan(theta/2).

I did it by finding sin(theta) and cos(theta) in terms of (theta/2) and then getting tan(theta/2) which only took me 4 lines, but i have this feeling there's a quicker way...

Did anyone do it a faster way?
 

photastic

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How did you guys do

cos(theta) = 1/5. Find tan(theta/2).

I did it by finding sin(theta) and cos(theta) in terms of (theta/2) and then getting tan(theta/2) which only took me 4 lines, but i have this feeling there's a quicker way...

Did anyone do it a faster way?
Lol, I did the longest method by finding tan(theta) then use the double angle of tan lolol
 

dunjaaa

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Let t=tan(x/2), (1-t^2)/(1+t^2) =1/5, cross multiply, it comes out in 1 line.
 

dunjaaa

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Also, is 0 < theta < 90? or 270 < theta < 360? Depending on which of these conditions are specified will determine whether tan(theta/2) is positive or negative.
 

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