Cssa mx1 (3 Viewers)

[muzeikchun852]

the only way u could have got it wrong wuld be if u entered one of the signs wrong. did u at least leave the answers on the page?

yeah.

 

[Dylanamali]

i finished with 30min to spare but still not feeling confident D:

Do you remember your answer for the red light q - binomial probability.

and did you do the last question 7b) tan, alpha stuff

 

[muzeikchun852]

lol this is equal to zero..

i swear my calculator is useless.

 

[Hermes1]

yeah.

kk. at least u wont lose any marks.

 

[HyperComplexxx]

Do you remember your answer for the red light q - binomial probability.

and did you do the last question 7b) tan, alpha stuff

prob i got 0.36, hope its right :S
the tan alpha one
i. show alpha = Tan-1(H/x) - Tan-1(h/x)
ii. diff and let = 0 to find max alpha (it said no testing so no test)
iii. tan both sides and simplify x^2 = Hh/2sqrt(Hh)

 

[Dylanamali]

sweet i got 0.36 aswell

I got part 1 im preety sure, just do simultaneous equations.

ah part ii and iii f'ed em up =/

 

[Dylanamali]

What was the circle geo answer...

The proof for congruency, i had AAS.

 

[Drongoski]

(2+root3)^3 - 15 (2+root3) + 4

btw, it's a sharp calculator.

Now we can see why you had problem. Yr Sharp calculator probably gave answer

That's for all intent and purposes zero. When your calculator computed , an irrational number it had to round the value to say 12 decimal places, so there is a discrepancy from the "true" value pf 1.73205 . . . . (forever) - so you can never represent the exact value with a finite number of digits. That's why overall you had a small "nonzero" final value.

 

[muzeikchun852]

the tan alpha one
i. show alpha = Tan-1(H/x) - Tan-1(h/x)
ii. diff and let = 0 to find max alpha (it said no testing so no test)
iii. tan both sides and simplify x^2 = Hh/2sqrt(Hh)

i. you look at the triangle that were given. and substitute the angles corresponded to it.
Tan-1(H/x) - Tan-1(h/x)
= alpha + theta - theta
= alpha

Now we can see why you had problem. Yr Sharp calculator probably gave answer

That's for all intent and purposes zero. When your calculator computed , an irrational number it had to round the value to say 12 decimal places, so there is a discrepancy from the "true" value pf 1.73205 . . . . (forever) - so you can never represent the exact value with a finite number of digits. That's why overall you had a small "nonzero" final value.

okay. i'm throwing my sharp and swapping over to casio after hsc.

 

[_deloso]

Re: CSSA Maths Ext 1 2011

http://community.boredofstudies.org/showthread.php/262636-Cssa-mx1

I know they're discussig bout it there but that thread was started yesterday.. before the exams! This is a legit forum dedicated for the exam today lol

 

[HyperComplexxx]

What was the circle geo answer...

The proof for congruency, i had AAS.

yea same
i spent like friggen 10min on the 1 marker (ii) of the circle question, i didn't read carefully and never knew the triangles were given to be congruent

 

[Dylanamali]

Did the actually say that the triangles were congruent? (The two mini triangles)
In ii) I actually proved they were congruent/isoscles then did my proof.

 

[muzeikchun852]

Did the actually say that the triangles were congruent? (The two mini triangles)
In ii) I actually proved they were congruent/isoscles then did my proof.

you use the answer in (i) and then the angle on the left hand side will be the same as the corresponding angle in the congruent triangle. after that vertically opposites angles and finish.

 

[HyperComplexxx]

im pretty sure it said so at the really end of that chunky paragraph

 

[dela_]

What was the circle geo answer...

The proof for congruency, i had AAS.

I used AAS aswell.

 

[brettymaccc]

I used RHS and proved alpha to be 45, giving the angle in the semicircle to be 2alpha, therefore making it a right angle. :s

 

[Omnipotence]

ewww maths. Please move it to the right section.

 

[jamesfirst]

What was the circle geo answer...

The proof for congruency, i had AAS.

All my friends got AAS


I was the only one who did SAS...

and did you do the last question 7b) tan, alpha stuff

I got 7 b) iii) definitely correct. But I'm not sure about 7 b) ii). I got the answer but I come some other shit at the end like . x^2 = hx + Hh + blah blah I dk


So I just made the big chuncky shit at the end = 0 and I did hence x^2 = blah blah blah


looooooooooooooool hope I get a full mark for that.

 

[taeyang]

so what were parts (a) and (b) for q7 and q6 of the test? was there anything that was very tricky?

 

[jamesfirst]

so what were parts (a) and (b) for q7 and q6 of the test? was there anything that was very tricky?

Q7 was a bit tricky.