Mathematics: Post your doubts here!

[mrpaudel]

For 4 i hope u can do i) .....and for ii)
Look at the values...27^y can be written as 3^3y..also as (3^y)^3...so..if u substitute 3^y as x..it would b the above equation.....so from above equation, we see..factors are -2 -3/4 and 2/3...negatives values are not possible..so 3^y=2/3 giving y= -0.369

 

[mrpaudel]

O...i didnot see 9 ii)...for 9 ii)
a) use...8Cos^4A-3=1.......and get it from here..
b)Use Cos^4A= 4Cos2A+Cos4A+3/8 and integrate...!!

 

[IgoforA]

how to find the factors -2,-3/4 & 2/3 for q4?

 

[IgoforA]

still i don't understand with q9. can you send me with an image form.. tq

 

[IgoforA]

another one from same year.. please help.

 

[Muhammad Talha]

Yr where r the helpful students ov thz forum?????
I want answers to my ques......!!!

 

[shressubha]

On any occasion when a particular gymnast performs a certain routine, the probability that she will
perform it correctly is 0.65, independently of all other occasions.
(i) Find the probability that she will perform the routine correctly on exactly 5 occasions out of 7.
[2]
(ii) On one day she performs the routine 50 times. Use a suitable approximation to estimate the
probability that she will perform the routine correctly on fewer than 29 occasions. [5]
(iii) On another day she performs the routine n times. Find the smallest value of n for which the
expected number of correct performances is at least 8. [2]

 

[shressubha]

A summary of 24 observations of x gave the following information:
Σ(x −a) = −73.2 and Σ(x −a)2 = 2115.
The mean of these values of x is 8.95.
(i) Find the value of the constant a. [2]
(ii) Find the standard deviation of these values of x. [2]

 

[XPFMember]

Assalamoaaikum!!

Well, I see there's no one to answer the queries, So those of you who are still waiting for the replies, post your questions again. I'll try to have a look at them in 2-3 days..inshaAllah ..though I can't gurantee if I'll be able to solve all.

P.S. I have just finished algebra and trigonometry of P3 so cant help with other chapters of P3!

 

[IgoforA]

for shressubha. poor quality sorry..

 

[pranjal091994]

Hi can someone help me with question 10)ii) from the Pure Maths paper 3..May/june 05..Thanks a lot

 

[sagystu]

limiting equlibrium means that the particle is about to move , right ?


well if its true then if i keep the same conditions of the limting equilibrium do the particle actually move or not ?
:%)

if ur answer is it deos moe then take a look at paper 4 nop v2 ;4
if it doesnt move please tell me why and thanks in advance
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
my 2nd question is the about the friction and cooficiant of friction i simplyy don't get it how does it increase also if u can see jo1 no 5 paper 4 if u can get it please answer the question 5


again i'd to thank in advance :wink:

 

[IgoforA]

to: pranjal.. hope u understand

 

[hassaan123]

 

[hassaan123]

A small trading company made a profi t of $250 000 in the year 2000. The company considered two different plans , plan A and plan B, for increasing its profits . Under plan A , the annual profit would increase each year by 5% of its value in the preceding year. Find, for plan A, (i) the profit for the year 2008, (ii) the total profit f or the 10 years 2000 to 2009 inclusive. Under plan B, the annual profi t would increase e ac h yea r by a constant amount $ D . (iii) Find t he value of D for w hich the t otal profit f or the 10 years 2000 to 2009 inclusive would be the same for both plans.

 

[mrpaudel]

how to find the factors -2,-3/4 & 2/3 for q4?

Since question says f(-2)=0, so...x+2 is one of the factor...now divide f(x) by X+2 to get the result which will be a quadratic...now i think u can factorise quadratic...now if u get (4x+3) as another factor, then x=-3/4 ..isn't it...!! i think u can do it now...!!

 

[mrpaudel]

still i don't understand with q9. can you send me with an image form.. tq

State precisely which one u didnot understand...!! question number 9 all??? or i or ii or..sth like this..plz mention it...!! for any question in writing form, wait few more hours, i will do it...

 

[mrpaudel]

u didnot mention marks...so i dont know the method may be longer...if u have mentioned marks too, i would have thought accordingly for any questions with less mark...well..here are the answers...

i) Slope of AD=slope of BC, u can find it..and find a equation of line BC
and then, CD and BC are perpendicular...so since u know the slope of BC, u can find the slope of CD..and find the equation of CD...solve two equations u get the co ordinate of C

ii) U have the equation of CD.....now...find the equation of AB...and solve it...u will get E

iii) Area of triangle= 1/2 * base * height i.e 1/2 * (17-1) * (Y coordinate of E-10)
and area of trapezium= 1/2 * sum of parallel sides * perpendicular length between them i.e =1/2* {(17-1)+(X coordinate of C -4)} *( Y coordinate of C-10)

I Assume u can find the slope and equations above..so i didnot calculate..!! hope that helped!!

 

[mrpaudel]

Hi can someone help me with question 10)ii) from the Pure Maths paper 3..May/june 05..Thanks a lot

dude u want the answer..not us...so if u want others to answer ur question...plz put the link....!!

 

[mrpaudel]

A summary of 24 observations of x gave the following information:
Σ(x −a) = −73.2 and Σ(x −a)2 = 2115.
The mean of these values of x is 8.95.
(i) Find the value of the constant a. [2]
(ii) Find the standard deviation of these values of x. [2]

U can find the formula in the book...look at it..!!! only the formula matters here..!!