integrate by parts ln(x)/x^3

The question states to use integration by parts. So first we recall the integration by parts formula is integrate(u(x)v'(x)  dx)=     (v(x)u(x))    -    integrate(u'(x)v(x)   dx)+c (note these integrals are with respect to x.. u(x) v(x) are functions of x and u'(x)=du/dx). To integrate ln(x)/x^3 notice that ln(x)/x^3 can be written as ln(x)*1/x^3. Then we let u(x)=ln(x) as we can differentiate ln(x) to 1/x but cannot easily integrate ln(x). So v(x)=1/x^3 Putting this into the formula we get integrate(ln(x)/x^3  dx)=  -0.5x^(-2) *ln(x)-integrate(-0.5x^(-2)*x^(-1)  dx)+c=  -0.5ln(x)/x^2+1/(4x^2)+c

Answered by Prit S. Maths tutor

2926 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

A triangle has sides A, B and C. The side BC has length 20cm, the angle ABC is 50 deg and angle BAC is 68 deg. a) Show that the length of AC is 16.5cm, correct to three significant figures. b) The midpoint of BC is M, hence find the length of AM


g(x) = x/(x+3) + 3(2x+1)/(x^2 +x - 6) a)Show that g(x) =(x+1)/(x-2), x>3 b)Find the range of g c)Find the exact value of a for which g(a)=g^(-1)(a).


Integrate Sin^2(x)


How do you prove by contradiction the irrationality of surds. Use sqrt 2 as an example.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences