Mathematics: Post your doubts here!

[Talha Irfan]

As only 0! and 1!=1, n(n-1)(n-2) ÷ (n-4) will be equal to 0 or 1.
With an equation with zero you get n=1 or 2 and with 1 you get n=-0.89

How did you equate the expression with zero? and its divided by (n - 4)!

 

[forget_me.not]

you take w= a + ib and w* = a -ib and put these values in the equation, simplify it and you will get the answer!

simplification is the problem!!! how do u do it?? O_O

 

[forget_me.not]

you take w= a + ib and w* = a -ib and put these values in the equation, simplify it and you will get the answer!

in the ms, it's written that u have to form 2 linear equations using real part and imaginary part. But i don't know how to do that

 

[syed1995]

I need a genius to solve this equation :

[n(n-1)(n-2)] ÷ (n-4)! = 1

Tell the source of the question and I will tell you the solution

 

[Champ101]

in the ms, it's written that u have to form 2 linear equations using real part and imaginary part. But i don't know how to do that

okok here you go:

3(a+ib) + 2i(a-ib) = 17+8i
Lets simplify the LHS first,
3a+3ib+ 2ai -2bi^2
3a+2b+(2a+3b)i = 17 +8i

now you get two linear equation:
3a+2b = 17 and 2a+3b = 8

hope you can solve now!!

 

[Lostsoul]

i hope tomorrows paper is one of the easiest ones

 

[Ahmed Aqdam]

How did you equate the expression with zero? and its divided by (n - 4)!

Sorry, I misread the question. I took '!' after the n(n-1)(n-2)] ÷ (n-4). According to the question, n=10

 

[Serenia]

Hello!

Can anyone please solve question 6 ii) on this Pure Maths 3 exam? I really can't figure it out.

Thanks in advance.


http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s13_qp_32.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s13_ms_32.pdf

 

[UXm@N]

Please koi yeh explain karde....
!!!

 

[Ahmed Aqdam]

Please koi yeh explain karde....
!!!

The 6 plastic mugs can be arranged in 6! ways. The 3 china mugs have 7 spaces so they can be arranged in 7P3 ways. Multiply them

 

[Sean002]

Hello!

Can anyone please solve question 6 ii) on this Pure Maths 3 exam? I really can't figure it out.

Thanks in advance.


http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s13_qp_32.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s13_ms_32.pdf

 

[Serenia]

Thank you so much, you're a life saver. And very well explained.

 

[Raghad Dia]

Hello, does anyone know how to solve questions related to vectors and planes using the ratio way?

 

[A star]

Tell the source of the question and I will tell you the solution

sir ap ka solution

 

[daredevil]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w13_qp_33.pdf

Q2... anybody? -.-

 

[unique111]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w13_qp_33.pdf

Q2... anybody? -.-

And at the end replace value of u. Answer should be in terms of x.

 

[MaRyy xD]

http://i.imgur.com/U8a8wmp.jpg

You basically have to eliminate either u or v from the equations and solve simultaneously. You could have also solved it by eliminating u like:
u + 2v = 2i - the first equation
Making u the subject:
u = 2i - 2v - (1)
As the other equation given is :
iu + v = 3 - (2)
Substitute (1) into (2):
i(2i-2v) + v = 3
-2 -2iv + v = 3
v - 2iv = 5
Making v the subject
v(1-2i) = 5
v= 5/(1-2i) - this is the second form given in the mark scheme



http://i.imgur.com/Ouotvyn.jpg

Edit: Er... if you were talking about graphing the argand diagrams question then it's lost on me too. Maybe these resources might help on graphing complex numbers in exponential form:
http://tutorial.math.lamar.edu/Extras/ComplexPrimer/Forms.aspx
http://www.intmath.com/complex-numbers/5-exponential-form.php
There are too many links; google "complex numbers +exponential form" for more resources

Thankyouuuuuuuuuuuuuu mannn.. I will see it later. mmm do we have to draw the arg diagram on a graph pper in the exam or what?

 

[MaRyy xD]

I'm confused. How did you get the points from w?

 

[daredevil]

And at the end replace value of u. Answer should be in terms of x.

okaay.... a question...

won't it be like :

(u-1)/u = 1 - (1/u) ???

 

[UXm@N]

Some one explain this please... need full explanation ...!!