# Definite Integration HelpWatch

This discussion is closed.
#1
I need help with this question. Any pointers are very much appreciated.

Evaluate the following definite integral:

(x - 3/x) ^2 dx .. limits are 6 and 3.

Tut.
0
13 years ago
#2
wouldnt it be (x-3/x)^2

(x-3/x)(x-3/x)
x^2 - 3x/x - 3x/x + 9/x^2
x^2 - 6 +9/x^2

and then integrate that?
0
13 years ago
#3
integral (x - 3/x) ^2 dx = integral (x^2 + 9/x^2 - 2(x)(3/x)) dx
= integral (x^2 + 9/x^2 - 6) dx
=(x^3)/3-9/x-6x (+c)
apply limits now
0
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