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

4460 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

How do I differentiate sin^2(x)?


What is the equation of the curve that has gradient dy/dx=(4x-5) and passes through the point (3,7)?


Two lines have equations r = (1,4,1)+s(-1,2,2) and r = (2,8,2)+t(1,3,5). Show that these lines are skew.


Below is a question from the Edexcel Maths Core 1 textbook, Solve the equation x^2 + 8x + 10 = 0 using completing the square.


We're here to help

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

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning