Maths paper 12 ???

[mak kings]

Im losing 15-20 marks. Wud I still get an A if I do well in S1 :s :'(

 

[thementor]

Im losing 15-20 marks. Wud I still get an A if I do well in S1 :s :'(

Yes, very easily

 

[M.Kabir Nawaz]

Please can anybody tell me how was I suppose to do question regarding shaded area?????

 

[siraj acharya]

area of triangle =area of segment
that will give you the value of p and for part 2 you had to use theta =l/r and by caluclating the value of l .The perimeter would be l+2r .I did it that way

 

[mak kings]

Yes, very easily

Thnks bro . That was some encouragement

 

[Hedwig]

could you tell me how much mark they might cut for forgetting the negative sign in the reflex angle answer? i did the whole question with the acute angle. is it completely wrong?

 

[siraj acharya]

which question ?

 

[Hedwig]

please, can anyone tell me how much mark the examiners will cut if i answer according to acute angle and not reflex angle? my answer's correct, except that i forgot the negative sign.

 

[Hedwig]

the one with the cos theta reflex angle.

 

[siraj acharya]

the one where we had to prove tan(theeta) in first part and solve in the next part what I did was I subsituted it with tan so it was like tan(theta)=-2
theta =tan inverse (-2) and it was -63.43 .I dint converted it to positive and used the same value so I will lose marks in this

 

[Wolfgangs]

for the Q2 ii the tan x = sq root (1-p^2)/p right? since both negative signs cancel each other out, right?

 

[Princess Raven]

Which reflux angle question?

 

[thementor]

for the Q2 ii the tan x = sq root (1-p^2)/p right? since both negative signs cancel each other out, right?

seriously man no. the tan will be negative. they don't cancel out

 

[Hedwig]

yes they don't. cos theta was k. no minus. but since its a reflex angle, sin theta and tan theta will come in minus. i forgot to do that! now, tel me how much mark they might cut. it was 5 marks in total.

 

[Princess Raven]

WHAAT?? Why will tan be negative!! We never took it like that

seriously man no. the tan will be negative. they don't cancel out

 

[Hedwig]

because its a reflex angle with cos theta.

 

[Hedwig]

what was the answer for vector OD?

 

[siraj acharya]

cos(theta)=k
sin(theta)= under root (1-k^2)
tan(theta)=under root (1-k^2)/k .so why negative ???

 

[Princess Raven]

because its a reflex angle with cos theta.

How do u know that :/

 

[Princess Raven]

cos(theta)=k
sin(theta)= under root (1-k^2)
tan(theta)=under root (1-k^2)/k .so why negative ???

Yea that's what I got too