Use integration by parts to find the value of definite integral between 5 and 1 (3x/root(2x-1))dx

use the formula integral(uv') = uv - integral(vu') so the tricky integral can be avoided (this formula can be derived from integrating the product rule) so in these questions all you need to look for is what can be differentiated out (might take more than one differentiation though).If the question is put in the form:integral(3x(2x-1)-0.5)dxthe term we can differentiate out an x from becomes clearer, its the 3x which will be the u in the equation and therefore the (2x-1)-0.5 will be the vlooking at the equation (2x - 1)-0.5 is now v'. it needs to be integrated using the reverse chain rule in order to find v:v' = (ax+b)nv = (ax+b)n+1/a(n+1)
v' = (2x - 1)-0.5 u = 3x v = 2
0.5(2x - 1)0.5 u' = 3
now plug the values into the equation:[3x(2x-1)0.5 -integral(3(2x-1)0.5)]51which now can be easily integrated using the reverse chain rule again:[3x(2x-1)0.5 -(3/3(2x-1)1.5)]51then just sub in x=5 and x =1 and subtract for the definite integral:(15*3 - 27) - (3-1)=16

Answered by Matthew G. Maths tutor

5044 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

How do I find the maxima and minima of f(x) = e^(x^2)?


The line l1 has equation 4y - 3x = 10. Line l2 passes through points (5, -1) and (-1, 8). Determine whether the lines l1 and l2 are parallel, perpendicular or neither.


log3 (9y + b) – log3 (2y – b) = 2, Find y in terms of b.


How do I remember the trigonometry identities from C3 in the exam?


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences