Mathematics: Post your doubts here!

[PhyZac]

i have to find 3 values of x and y to plot a graph...but they shud be in whole number.
11 x + 16y= 176

(16,0)
(0,11)

These are two.

 

[PANDA-]

(16,0)
(0,11)

These are two.

That's enough really because it's a straight line lol, no use of a third point

 

[Rutzaba]

(16,0)
(0,11)

These are two.

wat is this p1?

 

[syed1995]

anyone helping?

Well knowing you.. you would have gotten this figured by now .. but here's the solution anyway..

You will find the gradients of the tangents to the curve..

m of tangents = 1.5 and 0.75

then tan-1(gradient 1) - tan-1(gradient 2)
tan^-1 (1.5) - tan^-1(0.75)
56.3 - 36.9
= 19.4 Degrees

 

[champ-student]

(16,0)
(0,11)

These are two.

oooo....i have watd so much tym wid my calculator...thx a lot..^_^

That's enough really because it's a straight line lol, no use of a third point

thx ...thx...ty sooooo much

 

[PhyZac]

wat is this p1?

Well I don't know. But it can be anything.

 

[Rutzaba]

Well knowing you.. you would have gotten this figured by now .. but here's the solution anyway..

You will find the gradients of the tangents to the curve..

m of tangents = 1.5 and 0.75

then tan-1(gradient 1) - tan-1(gradient 2)
tan^-1 (1.5) - tan^-1(0.75)
56.3 - 36.9
= 19.4 Degrees

dude.. and guys at random... post krne se pehle dekkh liya karo ke kisi aur ne swal ka jawab tou nhi dde dya.. besides i was asking fr sumone else... thnkoo anyways buddy

 

[Rutzaba]

Well I don't know. But it can be anything.

lawl then how did u get the answer

 

[Rutzaba]

Well knowing you.. you would have gotten this figured by now .. but here's the solution anyway..

thnks fr da compliments

 

[PhyZac]

lawl then how did u get the answer

Umm, it is just finding points on a line, and I go for two points always, when x is 0 and when y is 0.

 

[syed1995]

dude.. and guys at random... post krne se pehle dekkh liya karo ke kisi aur ne swal ka jawab tou nhi dde dya.. besides i was asking fr sumone else... thnkoo anyways buddy

didn't feel like reading 3 pages

<--- is too lazy

 

[Rutzaba]

didn't feel like reading 3 pages

<--- is too lazy

u need not go bak three pages... just the top of this page actually

 

[Rutzaba]

Umm, it is just finding points on a line, and I go for two points always, when x is 0 and when y is 0.

le mai kiya hare kerri rocket science ay! xD

 

[Sanis]

i always have trouble in trigonometry ... i reached into 3sinxcosx=1 .. i checked the mark scheme x=0.365 radians .. when verifying it turns to be correct but however i don't know how I am supposed to reach this value when sin and cos are multiplied .. PLZ HELP URGENTLY thanks further

 

[PhyZac]

i always have trouble in trigonometry ... i reached into 3sinxcosx=1 .. i checked the mark scheme x=0.365 radians .. when verifying it turns to be correct but however i don't know how I am supposed to reach this value when sin and cos are multiplied .. PLZ HELP URGENTLY thanks further

Can you give the very first step?

 

[Sanis]

Can you give the very first step?

3tanx.(cos^2)x=1

 

[PhyZac]

3tanx.(cos^2)x=1

Well, see, i got x=0.365 as one of the answers, but I am not sure my way is correct, very complicated as well as, not the only answer! Was there a range?

 

[Sanis]

Well, see, i got x=0.365 as one of the answers, but I am not sure my way is correct, very complicated as well as, not the only answer! Was there a range?

1.206 .. anyways nvm abt it im sure there is another solution for this .. thank you

 

[PhyZac]

1.206 .. anyways nvm abt it im sure there is another solution for this .. thank you

Well i got this value too!

Okay here is the way.

P.S, i dint use more than Pure 1 knowledge.!

3tanx(cos^2)= 1

3 sinxcosx = 1

since , sinx = √1-cos^2 [ from sin^2 + cos^2 = 1]

3 √1-cos^2 cosx = 1

√1-cos^2 = 1/3cosx

1 - cos^2 = (1/3cosx)^2

1 - cos^2 = 1/9cosx^2

(9cosx^2)1 - cos^2 = 1

9cos^2 - 9cos^4 = 1

9cos^4 - 9cos^2 + 1 = 0

then using quaradictic formula u get.

cos^2(x) = 0.87267 or cos^2 = 0.12732

cos x = √0.87267 or cos x = √0.12732

x = cos^-1 (√0.87267) or x = cos^-1 (√0.12732)

 

[Sanis]

Well, see, i got x=0.365 as one of the answers, but I am not sure my way is correct, very complicated as well as, not the only answer! Was there a range?

well i found it 3sinxcosx=1 .. u gotta pretend that sinxcosx = half sin 2 theta .. since since sin 2 theta = 2sincosx .. so we actually get 1.5 sin 2x = 1 .. sin 2x = 2/3 .. then x= 20.90 degrees and it turns to be correct that if u took math a2 u will know this formula