maths P3 twisted

[crash250]

someone knows the integral of cot^4 x dx

thanksssssssssssss

 

[abuhantash]

I believe that would be lnsin(4x) + c

 

[crash250]

how can u tell me step by step

 

[ahmed t]

i have no clue
do u mean cot4x or cot^4 x
first one wud be 1/4 ln sin4x
second one i have no clue

 

[crash250]

i mean the second one ahmed

 

[ahmed t]

where did u get it from nothing this hard in the pastpapers

 

[crash250]

iam trying to find a suitable form but its not working

 

[crash250]

pastpapers is from the past which means to me NOTHING WILL BE GENERATED FROM IT IN THE COMING EXAMS so i dont depend on it much

 

[ahmed t]

i dont even think this is in our syllabus
i tried everything, every identity and everything i cant seem to get it

 

[crash250]

guys we r gonna ****** in this exam ...i feel that

 

[crash250]

wht do u think ahmed

 

[ahmed t]

if something new comes then ok
but if its the usual paper then i think itll go well

 

[crash250]

hahaahahahahahahhaa

 

[ahmed t]

just say inshAllah it comes easy and inshAllah it will

 

[ahmed t]

im goin to sleep in a bit so if there is any other question i could do right now?

 

[crash250]

thnx buddy....bezenallah kolna moafqeen...la ekef allah nafsan elaws3aha

gd night ahmed

 

[Islu_jf]

yes guys i want questions.. please help..

I want to know how to find the postion vector..
i know it seems easy .. but my teacher never taught me vectors .. he was to busy trying to be a principle.. so i'm ******

i'll give an example in Question 7 OCT/NOV 2010 31.// Please.. ????

 

[lotto]

First find the line AB..(the vector equation {which should be r=OA+ t(OB-OA)} )

the since we dont know the position vector of a point 'P' which lies on the line AB; we just let it be equal to the vector eq of the line.

now you have OP and AB........rite

soo take direction vector of AB and the vector OP and since they are equal their dot product must be= zero....

hope that helps!!!

 

[spanishswan]

position vector eqn=> r=a+tb
where r is the position vector
a is the cordinate lying on the line
t is the scalar multiple
b is the direction vector
in this q7
a can b i + 2j +2k or OB
n b is vector ab (ob - oa) which is 2i-2j-2k
so the vector eqn is a+tb
since p is lying on this line.it will have the same position vector given as vector eqn above only the value of t will be different
to find t they have op is perpendicular to ab so op in terms of t as column vector multipled by colum vector of ab = 0 since d1.d2=0 for ppncularz.
find t from here n insert it in the vector eqn to find the position vector OP
hope this helps!

 

[Islu_jf]

omg... yes .. it workd.. thnks guys .. i reli hope this comes instead of perp. distance..
coz i can nvr get that.. :S
thnks again.. <3