Mathematics: Post your doubts here!

[A star]

thnakkks

canu answer my wuestion :/

 

[PANDA-]

Prove the identity (sin x + cos x)(1 − sin x cos x) ≡ sin3 x + cos3 x. [3]
(ii) Solve the equation (sin x + cos x)(1 − sin x cos x) = 9 sin3 x for 0◦ ≤ x ≤ 360◦. can anyone solve part (ii) i dont get it @A

Take sin3x + cos3x as (sinx + cosx)(1 - sinx cosx)
So you get...
sin3x + cos3x = 9sin3x

Divide both sides by sin3x

1 + cos3x/sin3x = 9
1 + tan3x = 9
tan 3x = 8
3x = tan^-1(8)
x= 27.6 <=== Is this correct?

 

[littlecloud11]

I tried my best to understand, but it is hard. I found this.
https://www.xtremepapers.com/commun...st-your-doubts-here.9599/page-323#post-485476

Thank you Thank you Thank you!
I got it.

 

[snowbrood]

Take sin3x + cos3x as (sinx + cosx)(1 - sinx cosx)
So you get...
sin3x + cos3x = 9sin3x

Divide both sides by sin3x

1 + cos3x/sin3x = 9
1 + tan3x = 9
tan 3x = 8
3x = tan^-1(8)
x= 27.6 <=== Is this correct?

answer is 26.6

 

[A star]

Prove the identity (sin x + cos x)(1 − sin x cos x) ≡ sin3 x + cos3 x. [3]
(ii) Solve the equation (sin x + cos x)(1 − sin x cos x) = 9 sin3 x for 0◦ ≤ x ≤ 360◦. can anyone solve part (ii) i dont get it @A

is it p1?

 

[snowbrood]

Take sin3x + cos3x as (sinx + cosx)(1 - sinx cosx)
So you get...
sin3x + cos3x = 9sin3x

Divide both sides by sin3x

1 + cos3x/sin3x = 9
1 + tan3x = 9
tan 3x = 8
3x = tan^-1(8)
x= 27.6 <=== Is this correct?

lol chutia me i have solved this on my own now thanks anyways

 

[snowbrood]

is it p1?

yea p1 dude

 

[A star]

i

yea p1 dude

am also gettting 26.6. what year did u take it from?

 

[haha101]

Guys . tommorow we all have P1 . So i was thinking why dont we share some tips that help us in solving papers . Let me the first to initiate :

1. co linear or parallel vectors have a ratio of k . E.G if a and b are co linear then a^/b^ =k .

 

[A star]

Guys . tommorow we al have P1 . So i was thiinking why dont we share some tips that hepl us in solving papers . Let me the first to initiate :

1. colinear of parallell vectors have a ratio of k . EG if a and b are colinear then a^/b^ =k .

what?

 

[PANDA-]

Guys . tommorow we al have P1 . So i was thiinking why dont we share some tips that hepl us in solving papers . Let me the first to initiate :

1. colinear of parallell vectors have a ratio of k . EG if a and b are colinear then a^/b^ =k .

I didn't get it.

 

[Sarah22]

I didn't get it.

Haha.. Me too

 

[Sarah22]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_s11_qp_12.pdf
Question- 10 (a)
Please.. Thank You

 

[haha101]

haha . Look if two vectors are collinear of parallel then they have a common ratio between them . suppose a=(2.4.6) and b=(1.2.3)

a/b =2 and so they are both collinear

 

[Beaconite007]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_s10_qp_11.pdf
Q1 please :c

 

[falcon678]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_11.pdf
Q1 please :c

(i) tan(pie - x)= -k
(ii) tan(pie/2 -x)= 1/k

i dun knw for last one thou....

 

[MustafaMotani]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_11.pdf
Q1 please :c

are they correct..
first two comes from the graph.. but i recommend yu learn it

 

[PANDA-]

haha . Look if two vectors are collinear of parallel then they have a common ratio between them . suppose a=(2.4.6) and b=(1.2.3)

a/b =2 and so they are both collinear

OR... Their unit vectors are equal.

 

[panoramafolks]

go to olevel-alevel.blogspot.com

http://olevel-alevel.blogspot.com/2013/04/alevel-mathematics-course-material.html
http://olevel-alevel.blogspot.com/2013/04/as-level-pure-math-and-statisics.html
http://olevel-alevel.blogspot.com/2013/02/as-level-pure-math-1-p1-study-guide.html
http://olevel-alevel.blogspot.com/2013/02/as-alevel-mathematics.html

 

[PhyZac]

Thank you Thank you Thank you!
I got it.

You are welcome, I am glad I did something to help you!!

Btw, ._. can you explain? like some steps are so weird to me.