Mathematics: Post your doubts here!

[parthrocks]

Which num.?

6th one first

 

[giligili]

Yo can someone plz help me with this question ( show steps ty):
solve the equation : 2 sin^2(x) -cos x - cos^2(x) 0<x<360

 

[Minato112]

6th one first

 

[parthrocks]

Hey minato112 u rock!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!for solving so damnnnn fast!!!

 

[Minato112]

Yo can someone plz help me with this question ( show steps ty):
solve the equation : 2 sin^2(x) -cos x - cos^2(x) 0<x<360

 

[Minato112]

Hey minato112 u rock!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!for solving so damnnnn fast!!!

No prob! What matters is that the answer is right

 

[bamteck]

Well... Are the answers correct?

Yeaaaahhhh ! You are too good man !

 

[Minato112]

Yeaaaahhhh ! You are too good man !

Oh well im not too good... What matters as I already said above is that the answers are right

 

[giligili]

ty a lot but i missed the question...the question is same expect with the addition of a sin x at the cos x place..its like : 2 sin^2(x) - sin x cos x - cos^2(x) 0<x<360
srry again but i got a lil question..in ur answer uve sent me for the 2 sin^2(x) - cos x - cos^2(x)..uve write cos inverse of 1 is equal to 48.2 ( by sending cos inverse on the other side and 131.8 on the other side..it gives u cos inverse of 1 as 48.2...my calculator give me for cos inverse of 1...0 ..ive done something wrong? again thanks for the fast answer

 

[Minato112]

ty a lot but i missed the question...the question is same expect with the addition of a sin x at the cos x place..its like : 2 sin^2(x) - sin x cos x - cos^2(x) 0<x<360
srry again but i got a lil question..in ur answer uve sent me for the 2 sin^2(x) - cos x - cos^2(x)..uve write cos inverse of 1 is equal to 48.2 ( by sending cos inverse on the other side and 131.8 on the other side..it gives u cos inverse of 1 as 48.2...my calculator give me for cos inverse of 1...0 ..ive done something wrong? again thanks for the fast answer

Oh yea srry I took cos inverse of (2/3) instead of cos inverse of 1. Urs is fine.

 

[giligili]

Oh yea srry I took cos inverse of (2/3) instead of cos inverse of 1. Urs is fine.

ok ty..iam looking forward to the other one ( 2 sin^2(x) - sin x cos x - cos^2(x) 0<x<360 ) ty in advance

 

[NouranAyman]

Anyone taking Maths AS in november? please help i wanna what level are u upto... exam in 20 days :C and im late in past papers but il catch up by this week....GoD! studying in vacations is damn hard :-/

 

[shanky631]

Here you go, the full solutions for your 1st order differential equation problem.

Hope it helps. Peace.

Yes it really helped. Thanks a lot.

 

[Minato112]

ok ty..iam looking forward to the other one ( 2 sin^2(x) - sin x cos x - cos^2(x) 0<x<360 ) ty in advance

Well srry for l8 rep., was busy yesterD.

=> 2 sin^2(x) - sin x cos x - cos^2(x) = 0
=> (Divide by cos^2 (x) everywhere) => 2 tan^2 (x) - tan x - 1 = 0
=> (2 tan x + 1) (tan x - 1) = 0
=> tan x = (-1/2) or tan x = 1

tan x = (-1/2) :

x = 180 + [*tan inverse* (1/2) ] = 206.6
or x = 360 + [*tan inverse* (1/2) ] = 333.4

tan x = 1 :

x = *tan inverse* (1) = 45
or x = 180 + [*tan inverse* (1) ] = 225

Hope It helps.

 

[parthrocks]

A question from statistics 2 chapter:-sampling in statistics 2

can sum1 plzz show me the steps!!and is Continuity correction required?
minato112
whitecorp
leadingguy
leosco1995
nightrider1993
smzimran

5. The masses of kilogram bags of flour produced in a factory have a normal distribution
with mean 1.005 kg and standard deviation 0.0082 kg. A shelf in a store is loaded with
22 of these bags, assumed to be random sample.
(a) Find the probability that a randomly chosen bags has mass less than 1 kg.
(b) Find the probability that the mean mass of the 22 bags is less than 1 kg
State, giving a reason, which of the above answers would be little changed if the
distribution of masses were not normal.

 

[daviruss]

assalamu 3alaikom guys, iam going to sit for my AS exam in oct/nov 2012 Mathematics (P1,M1) and seems that every thing is going great el7amdolilah, but iam just having trouble in trying to calculate the surface area or the volume of a figure , for example when a question comes asking abt to show that A= blah blah . and that find h in terms of r, for example , and then a diffrentiation question , the diff question is easy but the hardest thing for me is to find the SA so please help me! iam going to sit for my exam soon. Can u till me any tip for how to prepare for the math AS , P.S. i do solve PP's

 

[Ahmedm96]

does any one has post nov 2002 M1 and P1 marking schemes

 

[parthrocks]

A question from statistics 2 chapter:-sampling in statistics 2

can sum1 plzz show me the steps!!and is Continuity correction required?
minato112
whitecorp
leadingguy
leosco1995
nightrider1993
smzimran

5. The masses of kilogram bags of flour produced in a factory have a normal distribution
with mean 1.005 kg and standard deviation 0.0082 kg. A shelf in a store is loaded with
22 of these bags, assumed to be random sample.
(a) Find the probability that a randomly chosen bags has mass less than 1 kg.
(b) Find the probability that the mean mass of the 22 bags is less than 1 kg
State, giving a reason, which of the above answers would be little changed if the
distribution of masses were not normal.

Anyone reply plzzzzzz need it urgently

 

[giligili]

Well srry for l8 rep., was busy yesterD.

=> 2 sin^2(x) - sin x cos x - cos^2(x) = 0
=> (Divide by cos^2 (x) everywhere) => 2 tan^2 (x) - tan x - 1 = 0
=> (2 tan x + 1) (tan x - 1) = 0
=> tan x = (-1/2) or tan x = 1

tan x = (-1/2) :

x = 180 + [*tan inverse* (1/2) ] = 206.6
or x = 360 + [*tan inverse* (1/2) ] = 333.4

tan x = 1 :

x = *tan inverse* (1) = 45
or x = 180 + [*tan inverse* (1) ] = 225

Hope It helps.

ty very much for the reply late or not much appreciated

 

[Minato112]

ty very much for the reply late or not much appreciated

No prob.