Mathematics: Post your doubts here!

[Holmes]

Ok nevermind that. If you want a plane that is perpendicular to both, then the line of intersection of the two planes must act as a perpedicular to the third plane correct?
basically want to find the equation of that line and then we can proceed from there. We have point A on the line with y coordinate of 2 so lets find its x and y components
x+2+3z=8....x+3z=6
2x-2(2)+z=3....2x+z=7
rearrage the first equation to make x the subject
x=6-3z
substitute x into the second equation
2(6-3z)+z=7
12-5z=7
z=1
x=3
so A: (3,2,1)
Thats one part down. Now we need to find ANY other point on that line so we can figure out its direction. Let us take y=3
x+3+3z=8....x+3z=5
2x-2(3)+z=3....2x+z=9
rearrage the first equation to make x the subject
x=5-3z
substitute x into the second equataion
2(5-3z)+z=9
10-5z=9
z=0.2
x=4.4
so the other point is (4.4,3,0.2)
Let us find the direction of the line then:
[4.4i+3j+0.2k]-[3i+2j+k]=[1.4i+j-0.8k] This is the normal to the plane in question

setting up the cartesian equation of the plane: 1.4x+y-0.8z=[1.4i+j-0.8k].[3i,2j,k]

1.4x+y-0.8z=5.4
1.75x+1.25y-z=6.75
7x+5y-4z=27

Thanks boyz

 

[Holmes]

(b) part help plz
DudeWithoutName

 

[insharah]

i need help in a recent paper 2017 feb march paper 32
question number 5
any help would be appreciated
thank u in advance

 

[Hunzlah Malik]

i need help in a recent paper 2017 feb march paper 32
question number 5
any help would be appreciated
thank u in advance

Let me give it a try,
y=e^(-ax)tanx
dy/dx=(-a)(e^-ax)(tanx)+(e^-ax)(secx^2)=0
a(e^-ax)(tanx)=(e^-ax)(secx^2)
atanx=1+tanx^2 -- secx^2=1+tanx^2
tanx^2-atanx+1=0
solve it simultaneously.

 

[Hunzlah Malik]

https://papers.gceguide.com/A Levels/Mathematics (9709)/9709_s16_qp_61.pdf
Q5 part ii) 180 ==> 179.5
When exactly do we use continuity corrections?? Can someone quote some other questions?

You use these approximation when you are converting binomial to normal distribution.
you have to think yourself like if in binomial there is >180, then in normal it should be =>181.5
if in binomial there is <180 then in normal there is =<179.5
if in binomial there is =<180 then in normal there is =<181.5
Mean you have to make sure that the range in normal shouls contain the binomial range.
On the last page of Znotes there is approximation
Search Znotes in google

 

[DudeWithoutName]

View attachment 63635
View attachment 63636

(b) part help plz
DudeWithoutName

Parts A and B are attached below

 

[Holmes]

Parts A and B are attached below

THanks boy it was a huge help

 

[Holmes]

Q 9 (i) and (iii)





Anyone please help!

 

[Munguunuuu]

Does anyone who taking the S1 component 63 tomorrow? Any tips?

 

[xoxoxoxo123276]

Does anyone have the solved paper 12/9709/2018

 

[Hunzlah Malik]

View attachment 63642

View attachment 63643
Q 9 (i) and (iii)

View attachment 63644

View attachment 63645

Anyone please help!

 

[amina1300]

https://papers.gceguide.com/A Levels/Mathematics (9709)/9709_s17_qp_62.pdf
Q4 ms says P(score is 6) = P(3, 3)
= r^2 = 1/36
why r^2 !!

Q5 How did we get the value of Z? (other than the use of a calculator)

Q When using the probability table ..how do we use the section on the right-hand side which had ADD written on top of it. Is that number added at the last d.p value?

 

[MelvinW]

Hello in need of help for 9709_w10_qp_63 questions 6 and 7 i dont understand how to do them even the mark scheme doesnt help me .....

 

[Hunzlah Malik]

https://papers.gceguide.com/A Levels/Mathematics (9709)/9709_s17_qp_62.pdf
Q4 ms says P(score is 6) = P(3, 3)
= r^2 = 1/36
why r^2 !!

Q5 How did we get the value of Z? (other than the use of a calculator)

Q When using the probability table ..how do we use the section on the right-hand side which had ADD written on top of it. Is that number added at the last d.p value?

That very early, just wait for the answer till tomorrow.
Kiun ky kal paper hi or ab tumheen ye bateen yad aa rahi hain? :/

 

[Mts.99]

If in stem and leaf, lower quartile/upper quartile's position is lets say 7.25, do we take 8th value?

 

[Hunzlah Malik]

If in stem and leaf, lower quartile/upper quartile's position is lets say 7.25, do we take 8th value?

In Alevel it can't be in decimal. On this level there is only whole number. If you have Q from past paper I may help you.

 

[MIK3Y.]

hey need help with 4(ii) (b)

 

[ba-lock-ey]

anyone got the marking scheme for feb march 2018? Thanks

 

[Holmes]

anyone got the marking scheme for feb march 2018? Thanks

Which paper

 

[Holmes]

anyone got the marking scheme for feb march 2018? Thanks

Most are here:
https://drive.google.com/drive/folders/1-A53teIm6qZVmW9xnU9l1FMUvUqcgirH