how was maths P32

[AlphaCentauri]

WAT WAS QUESTION NO 4

Chill.

Perhaps polynomial one?

 

[anahita16]

!! I got only one too!!! but there were two
confirmed that wid my teacher

 

[vaishster]

yehh... we hav 2 find a =1 .... wat ws thhe second part of the q ??

 

[AlphaCentauri]

!! I got only one too!!! but there were two
confirmed that wid my teacher

I'm pretty sure there was one. There couldn't have been two acute angles, were there two, one would have been obtuse.

yehh... we hav 2 find a =1 .... wat ws thhe second part of the q ??

Oh that. You were required to find the two real roots. It's the second quadratic factor you obtain. The one given doesn't give any real root. I think it was -1 and -3.

 

[anahita16]

one answer was 10.sumfng...the other, which i got, was sixty sumfng.I'm not gonna be consoled till I see the ms with my own eyes. :O:

 

[anahita16]

I got -1 and -3 too.

 

[AlphaCentauri]

10? Are we talking about the same question?

First part where you had to transform into a double angle?

Anyway, forget it. There are other papers to prepare.

 

[vaishster]

me 2...

 

[vaishster]

wt question r u talkin bt .. ill tel u the answer

 

[anahita16]

Yeah.
I lost a mark due to trigonometry in P1 too. I had doubts right in the exam hall itself for p3, for the last part of the trigo question carried 5 marks, a bit too much for one angle only but I could not find any mistake or missing value back then. Now when I discussed the paper with friends and teacher...phew. Trigonometry is just not my thing I guess. Anyway you're right, let's just forget it.

 

[anahita16]

wt question r u talkin bt .. ill tel u the answer

The one where the first part we had to convert in the form R(cos x-alpha).
R=root 10
alpha= either 72 or 57 i forgot.

 

[vaishster]

R=root 10 .. angle ws71 .6

 

[AlphaCentauri]

Yes, same question Anahita. There was only one answer. I'm pretty sure. I discussed it with others too. Between 0 and 90 degrees. Perhaps your friends missed the domain?

What did you get Vaishter as final answer?

R and angle are the same for me.

 

[adzino]

any one remembers the question no. 3 and 4 please post it here...
and the vector part, i got 1/3 for the lambda, others got 3/8

 

[MW24595]

Nope. There were 2 answers for that trigo question. Both within the domain 0<theta<90.
it was Root 10 cos(2theta - 71.6)= 2
so, cos(2theta - 71.6) = 2/Root 10
2Theta - 71.6 = 50.77 OR -50.77, as cos(-x) = cos(x)
Theta = (50.77+71.6)/2 OR (-50.77+ 71.6)/2
Thus, Theta = 61.2 AND/ OR 10.4.

Kinda sucks when you miss something like that.
Anyway, Auragirl!
You mentioned earlier that your answer to the last question, the one about the greatest value for Arg Z for the points within the circle
to be 2.3 radians or arouuund, 132 Degrees.
Are you Sure?! I mean, REALLY sure? Because that's exactly what I wrote, and it's the only question I'm unsure of.

 

[MW24595]

any one remembers the question no. 3 and 4 please post it here...
and the vector part, i got 1/3 for the lambda, others got 3/8

Hmm, Lambda = 3/8 for sure. I substituted back into the original equation and it fit like a charm. Hard Luck, man. :/
And Questions 3 and 4? Hmm, where they the ones about Polynomials and Differential equations?

 

[adzino]

yea the differential eqn one i gues...
polynomial i did it right i guess . a=1
x= -1, -3

 

[AlphaCentauri]

Nope. There were 2 answers for that trigo question. Both within the domain 0<theta<90.
it was Root 10 cos(2theta - 71.6)= 2
so, cos(2theta - 71.6) = 2/Root 10
2Theta - 71.6 = 50.77 OR -50.77, as cos(-x) = cos(x)
Theta = (50.77+71.6)/2 OR (-50.77+ 71.6)/2
Thus, Theta = 61.2 AND/ OR 10.4.

Kinda sucks when you miss something like that.
Anyway, Auragirl!
You mentioned earlier that your answer to the last question, the one about the greatest value for Arg Z for the points within the circle
to be 2.3 radians or arouuund, 132 Degrees.
Are you Sure?! I mean, REALLY sure? Because that's exactly what I wrote, and it's the only question I'm unsure of.

Oh noo... yes, you are right. I just checked on a graph plotter! At least 2 marks gone. And I thought I finally made a perfect score for this one.
Sorry Anahita, you were right. Hm, I guess the friends I asked made the same silly mistake.

Yes, I'm sure 2.30. 132 too is good.

Thanks, for clearing about the trigo.

Anyway, the rest of the crying later. I gotta catch up in Stats. Thanks again!

 

[anahita16]

Not me mate...my friends were right!!! Even I was vehemently defending my 61.2 as the only ans. But when I substituted the other value in the equation, I did get 2.
This sucks...

MW24595, yeah I remember that answer, it was 2.3005, 2.30radians to 3 significant figures!

 

[nikhil000]

Hey everyone , Please predict the threshold...I guess it should be 57-60.