# p3 integrationWatch

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#1
hi would someone be able to help me with this question please

you have to find the integral using the substitution given:

integrate (x/(x+1))^2 dx ; u = x+1

thank you!
0
#2
also, how would you be able to change:

-ln(1/root2)

to

1/2ln2

thank you!
0
14 years ago
#3
(Original post by eek)
also, how would you be able to change:

-ln(1/root2)

to

1/2ln2

thank you!
-ln(1/rt2) = ln([1/rt2]^-1) = lnrt2 = 0.5ln2
0
14 years ago
#4
(Original post by eek)
hi would someone be able to help me with this question please

you have to find the integral using the substitution given:

integrate (x/(x+1))^2 dx ; u = x+1

thank you!

u=x+1, du/dx = 1, du=dx.
x=u-1

INT [(u-1)/(u)]^2 du = INT [1 - 1/u]^2 du = INT 1 - 2/u + u^-2 du
= u - 2lnu -u^-1 + C
= (x+1) -2ln(x+1) - 1/(x+1) + C
0
#5
yay...i got it!

0
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