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

4420 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Find the general solution to the differential equation '' (x^2 + 3x - 1) dy/dx = (2x + 3)y ''


Given that y > 0, find ∫((3y - 4)/y(3y + 2)) dy (taken from the Edexcel C4 2016 paper)


What is the probability that a leap year has 53 Sundays?


I struggle to simplify the following equation: (see answer)


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