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

MG

Related Maths A Level answers

All answers ▸

A particle P is projected vertically upwards from a point 20m above the ground with velocity 18m/s, no external forces act on it other than gravity. What will its speed be right before it hits the ground? Give your answer to one decimal place.


how do you do binomial expansion when the power is a negative


Show that the derivative of ln(x) = 1/x


find the value of dy/dx at the point (1,1) of the equation e^(2x)ln(y)=x+y-2