A curve has equation y = f(x) and passes through the point (4, 22). Given that f ′(x) = 3x^2 – 3x^(1/2) – 7, use integration to find f(x), giving each term in its simplest form.

Firstly we can use the difference rule to split f'(x) into three components which we can consider separately. Then using the knowledge that the integral of x^n is 1/(n+1)*x^(n+1) we get the expression for f(x) as x^3 - 2x^(3/2) - 7x + C where C is an unknown constant.We find C by using the other information the question gives us- that when x=4, y =22. Plugging this into f(x) gives us the equation 22 = 20 +C, so C = 2. The final expression is therefore f(x) = x^3 - 2x^(3/2) - 7x + 2.

AS
Answered by Abbey S. Maths tutor

3669 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

How do you know when to integrate by parts?


Two particles A and B of mass 2kg and 3kg respectively are moving head on. A is moving at 5m/s and B is moving at 4m/s. After the collision, A rebounds at 4m/s. What is the speed of B and what direction is it moving in?


How to find the reciprocal of a graph, such as y=cos(x)?


Differentiate a^x


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences