How do you integrate [((3x^2)+2x)/x^2]dx from 4 to 2?

1 Answer
May 6, 2015

Here's my version:
(no guarantee that it's right)

int_4^2(3x^2+2x)/(x^2) dx

=int_4^2 ( (3x^2)/(x^2) + (2x)/(x^2))dx

= int_4^2 (3x^2)/(x^2)dx + int_4^2 (2x)/(x^2)dx

= 3int_4^2(1)dx + 2int_4^2(1/x) dx

= 3*( x|_4^2 ) + 2*(ln|x||_4^2)

=3( 2-4) + 2 (ln(2)-ln(4))

=-6 + 2(0.693147 - 1.386794)

=-6 - 1.3863

= -7.3863