Mathematics: Post your doubts here!

[ahmed abdulla]

tan2x = sin2x/cos2x
integration of sin2x/cos2x = -0.5(ln(cos2x)+c = o.5ln(cos2x)^-1 +c = 0.5ln(sec2x) +c



use the double angle formula for this one
cos^2(x) = (cos2x+1)/2

can u ( plz ) post some of the formulas ... because i first time hear of double angle formula ! >> formulas which are not inside the book

 

[ahmed abdulla]

tan2x = sin2x/cos2x
integration of sin2x/cos2x = -0.5(ln(cos2x)+c = o.5ln(cos2x)^-1 +c = 0.5ln(sec2x) +c



use the double angle formula for this one
cos^2(x) = (cos2x+1)/2

can u ( plz ) post some of the formulas ... because i first time hear of double angle formula ! >> formulas which are not inside the book

 

[DumbIdiot]

can u ( plz ) post some of the formulas ... because i first time hear of double angle formula ! >> formulas which are not inside the book

sin2x = 2cosxsinx
cos2x = 2cos^2(x) -1
tan2x = (2tanx)/(1-tan^2(x))

 

[DumbIdiot]

tell me procedure..

let Z= 2x-Y
express : 3cos(Z)+4sin(Z)=2 in the form Rcos(Z-A) = 2
R = root(3^2 + 4^2) = 5
A = acrtan (4/3) = 53.1 degrees(convert to radian if you want to)
solve 5cos(Z-53.1) = 2

 

[ahmed abdulla]

sin2x = 2cosxsinx
cos2x = 2cos^2(x) -1
tan2x = (2tanx)/(1-tan^2(x))

thanks , but all this formulas are known ... i want stuff like double formula

 

[DumbIdiot]

thanks , but all this formulas are known ... i want stuff like double formula

what other double formula?
u mean cosec2x and stuff?

 

[ahmed abdulla]

what other double formula?
u mean cosec2x and stuff?

yep

 

[salvatore]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s11_qp_33.pdf
Could anyone please help me with qn no. 3 of this paper?
Its urgent.. thanks!

 

[Rutzaba]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s11_qp_33.pdf
Could anyone please help me with qn no. 3 of this paper?
Its urgent.. thanks!

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s11_qp_33.pdf
Could anyone please help me with qn no. 3 of this paper?
Its urgent.. thanks!

∫ (1-x) (e^-0.5x)
can also be written as
∫ e^0.5x +∫ (-xe^-0.5x)
break this into 2 parts the first integral can be solved by
∫ (e^-0.5x) = -2e^-0.5x ---- i
the second part
∫ (-xe^-0.5x)
apply by parts
u=x and its differential u'=1
dv= e^-0.5x and its integral and v= -2e^ -0.5x
apply
∫ u dv= uv- ∫v du
-2x e^-0.5x + ∫ 2 e^-0.5x
-2x e^-0.5x -4e^ -0.5x ---- ii
i+ii
(wch is minus)
-2e^ -0.5x - (-2x e^ -0.5x -4e^ -0.5x)
(-2e^ -0.5x) +(2x e^ -0.5x) +(4e^ -0.5x)
Now apply limit 1 and 0
and remember me in prayers plz i badly badly need it

 

[salvatore]

∫ (1-x) (e^-0.5x)
can also be written as
∫ e^0.5x +∫ (-xe^-0.5x)
break this into 2 parts the first integral can be solved by
∫ (e^-0.5x) = -2e^-0.5x ---- i
the second part
∫ (-xe^-0.5x)
apply by parts
u=x and its differential u'=1
dv= e^-0.5x and its integral and v= -2e^ -0.5x
apply
∫ u dv= uv- ∫v du
-2x e^-0.5x + ∫ 2 e^-0.5x
-2x e^-0.5x -4e^ -0.5x ---- ii
i+ii
(wch is minus)
-2e^ -0.5x - (-2x e^ -0.5x -4e^ -0.5x)
(-2e^ -0.5x) +(2x e^ -0.5x) +(4e^ -0.5x)
Now apply limit 1 and 0
and remember me in prayers plz i badly badly need it

Thanks s lot Rutzaba!!
I'll definitely remember you in prayers

 

[Rutzaba]

Thanks s lot Rutzaba!!
I'll definitely remember you in prayers

id b grateful

 

[Rutzaba]

can u help me with M2 >> q4
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s08_qp_5.pdf

listen i got 2 pprs tommz and one after that uni level.
im srry.

 

[Rutzaba]

can u help me with M2 >> q4
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s08_qp_5.pdf

besides i never gave mechanics ^_^

 

[saadgujjar]

a girl lives 500 meter from school.she sets out walking at 2 m/s but when she has walked a distance of x meter her speed has dropped to (2 - x/400 )m/s .how long does she take to get to school?answer is 6.5 minute plz solve

 

[Khadija_1234]

How do you square an equation like this? (x^2 -2x -3)
Please help

 

[saadgujjar]

a girl lives 500 meter from school.she sets
out walking at 2 m/s but when she has
walked a distance of x meter her speed has
dropped to (2 - x/400 )m/s .how long does
she take to get to school?answer is 6.5
minute plz solve

 

[mikail]

U need to square this quadratic equatiion: (x^2 -2x -3)

(x^2 - (2x+3) )^2 = x^2 - 2 (x)(2x+3) + (2x+3)^2


Now u can complete............

 

[ahmed abdulla]

U need to square this quadratic equatiion: (x^2 -2x -3)

(x^2 - (2x+3) )^2 = x^2 - 2 (x)(2x+3) + (2x+3)^2


Now u can complete............

heLp M2 >> q4
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s08_qp_5.pdf

 

[mikail]

U should use Moments

 

[mikail]

U should use Moments