maths p3 .. nov 10p33 .. please help

[Madiha :)]

can anyone please explain me part ii of this question ?
what region do v hav to shade ? and what wil b the radius of the circle? 5?

 

[WellWIshER]

CAN SOMEONE PLEASE INTEGRATE 2X/(X+1)

 

[ahmed t]

for madiha
find the point w on an argand diagram and w^2
then draw a btwn the two
draw a perpindicular bisector for this line
the < implies any point in this are will be either closer to w^2 or same distance btwn w and W^2
so u will shade the region closer to w^2

 

[ahmed t]

as for wellwisher i would say intergrate using sub makin u=x+1

but usually in the exam they would give u U=.....
u wouldnt have to make ur own substitution

 

[crash250]

excuse me ahmed t, this is a circle with radius 5 not perpendicular bisector

 

[ahmed t]

oh damn
thanks crash, didnt read the question properly sorry
so yes wat he says radius of 5 with center at point w^2 so all u do is shade the inside
once again thanks crash for pointing that out

 

[crash250]

for wellwisher...u can use integration by parts which is more systematic than substitution
2x.(1/x+1)..that will be better since examiners look for it

 

[crash250]

fine ahmed t its ok ..u have done a wonderful job sofar

 

[ahmed t]

i actually find substitution easier than parts, for some reason

 

[crash250]

i frankly see that we cant apply substitution always in (integration by parts ) form ...the examiners would reject it obviously.
we should see if parts than be applied first than we think of substitution since some equations require 2 substitution which would be tough logically
by the way they dont always give us the substiitution key
refer past papers

 

[WellWIshER]

cheers guys

 

[Madiha :)]

thanku ahmed .. btw v wil have to shade the inside of the whole circle ? or sum particular region?

 

[ahmed t]

nope the whole circle

 

[Madiha :)]

okaay thanx=)