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#1 Help Me ! » Probabilty Distribution » 2009-06-21 00:34:00

Angel Rox
Replies: 1

Let X represents the spot on a die,
Find the probability distribution of X and variance (σ^2 x = Var (x))


need some hints in this one ... Thanx in advance

#2 Help Me ! » Need Help Urgently...!! » 2009-05-25 00:24:41

Angel Rox
Replies: 0

Q1 - Evaluate the iterated integral by converting to polar coordinates

∫0 to 2 ∫-Sqrt 4-x^2 to Sqrt 4-x^2 e^(-x^2-y^2) dy dx

The region of integration is bounded by
-Sqrt 4-x^2 ≤ y ≤ Sqrt 4-x^2 and 0 ≤ x ≤ 2



Q2 - Evaluate the triple integral ∫∫R∫ OR ∫∫∫R f(x,y,z)dV

With f(x,y,z)=Sqrt y -3z^2

Q = {(x,y,z)/2 ≤ x ≤ 3, 0≤ y ≤1, -1≤ z ≤1 }

#3 Help Me ! » need help urgently... » 2009-04-08 21:18:05

Angel Rox
Replies: 3

Q1 - Find the critical points of the function  f(x,y) = x^2 + 2y^2 - x^2y and then classify them into relative maxima, relative minima and saddle points.


Q2 - Let f(x,y) = xy - x - y + 3 and R is the triangular region with vertices (0, 0), (2, 0) and (0, 4). Find the interior and boundary points only at which the absolute extrema of f(x,y) can occur.

#4 Re: Help Me ! » need help Urgently.. Time till tommorow :( » 2009-03-29 21:34:26

and yeah in Q2 .. plz correct my answer ..

•    Assuming the spherical coordinates are (r,theta,phi), rectangular coordinates are:
x=r sin(theta)cos(phi)=4 * sin(3.14/2) cos(3.14/6)=3.464
y=r sin(theta)sin(phi)=4 * sin(3.14/2) sin(3.14/6)=2
z=r cos(theta)=4 * cos(3.14/2)=0

Cylindrical coordinates are:
rho = r sin(theta)=4 * sin(3.14/2)=4
phi = phi=3.14/6
z= r cos (theta)=4 * cos(3.14/2)=0

To convert back from cylindrical coordinates
r=sqrt{rho^2+z^2}=rho=4
theta=atan2 {rho,z}=atan2(4,0)=3.14/2
phi=phi=3.14/6

#5 Re: Help Me ! » need help Urgently.. Time till tommorow :( » 2009-03-29 21:32:42

Thanx alot dear... It was really helpful... Thanks once again!

#6 Help Me ! » need help Urgently.. Time till tommorow :( » 2009-03-29 02:01:22

Angel Rox
Replies: 4

Q1 - Use chain rule to find df/dx , df/dy

For f(r,s,v) = r^3 + s + v^2  ,  where r = xe^y  , s = ye^x and v = x^2 y



Q2 - Spherical coordinates of a point are (4 , π/6 , π/2)



a - Convert spherical coordinates to rectangular coordinates

b - Convert spherical coordinates to cylinderical coordinates

c - Verify your answer by converting back spherical coordinates from anyone of these, that is , either from rectangular or cylinderical coordinates.



I need detailed answer for Question no. 1 coz i dont know how to start it.. and for Question 2 just hints for that .. Thanks in advance

#7 Re: Help Me ! » Converging or diverging..?? » 2009-01-29 02:19:27

Thanx Alot... but somebody told this question to me like that

now the difficulty is that am totally blank and confused in this question... i tried alot to figure it out but i couldnt find any example related to this question in my solved notes and hand outs... so plz kindly help me out... if u can write step by step procedure .. It'll be of great help...

#8 Help Me ! » Converging or diverging..?? » 2009-01-28 16:45:41

Angel Rox
Replies: 5

Determine whether the series:

25^-n+2 . 16^n+1 converges or diverges. If it converges then find its sum


Can I have some hints in solving this question..:/

#9 Re: Help Me ! » Help Needed.. » 2009-01-25 16:16:00

Thanx alot... really appreciated...

#10 Help Me ! » Help Needed.. » 2009-01-24 08:26:30

Angel Rox
Replies: 2

Q1 - Find the volume of the solids generated by revolving the regions bounded by the lines and curves about x-axis

y=√cosx where 0 ≤ x ≤ π/2 and y=0 , x=0


Q2 - Evaluate the integral


e^-√x/√x dx


Thanx in adavnce... smile

#11 Help Me ! » Need help in solving...urgent plz » 2008-12-30 17:38:29

Angel Rox
Replies: 1

Q1 - Use Newton's method to find the value of x for the function f(x)=2x^2 + 4x - 3 = 0 ; x > 0
Note : Perform only 3 iterations.



Q2 - Evaluate the integral ∫ (1 + sinx)^6 cosxdx by proper substitution.




Q3 - Evaluate the sum ∑ k(k - 2)(k + 2) using the required theorems.


Note on this sign "∑" on the upper side it is 35 and on the lower side it is k-1....I dont know how to use the tags here coz am new...sorry plz...

Help me in thiseek

#12 Help Me ! » Need help Urgently!!!!! » 2008-12-11 16:34:24

Angel Rox
Replies: 1

Q1- The distance traveled by an object at time t ≥ 0 is s = f(t) = t^2 where s is in meter (m) and t in seconds (sec). Find the instantaneous velocity of the object at t = 2sec


Q2- Find the natural domain of the given function

h(x) = 1/1-sinx

Q3- What are the points of discontinuity for the function f(x)=x+5/x^2-1 ?

swear

#13 Help Me ! » Need Help » 2008-12-11 01:35:40

Angel Rox
Replies: 1

Q1- Find the x-coordinate of the point on the graph of y=x^2 where the tangent line is parallel to the secant line that cuts the curve at x=-1 and x=2

Q2- Solve | x −3|^2 −4| x −3|=12 for x.

#15 Help Me ! » Help me out with this .... its really urgent » 2008-11-23 20:45:33

Angel Rox
Replies: 2

If f(4)=3 & f'(4)=-5, find g'(4). where g(x) = √x  f(x)?

#16 Re: Help Me ! » Help Me With This!! » 2008-11-10 23:21:22

It is Urgent Man...If u can be of some help then plz write the solution.... I'll appreciate that... smile

#17 Re: Help Me ! » Help Me With This!! » 2008-11-10 21:55:15

So no body can solve the 1st Question that Wizard Posted...

It was Prove that the function f(x)=x^3-2x+3 is continuous

Plz I too need the solution....Its really urgent !!!swear

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