Consider the function f(x) = 2/3 x^3 + bx^2 + 2x + 3, where b is some undetermined coefficient:

a) Find f ' (x) and f ''(x). f' = 2x2 + 2bx + 2f'' = 4x + 2bb) You are given that f(x) has a stationary point at x = 2. Use this information to find b.2x2 + 2bx + 2, x=2Stationary point is when f' = 02(2)2 + 2b(2) + 2 = 08 + 4b + 2 = 04b = -10b = -2.5c) Find the coordinates of the other stationary point.2x2 - 5x + 2 = 0(2x−1)(x−2)x = 0.5 or x=2Sub x = 0.5 into original function to get: (0.5 , 83/24)

CP
Answered by Charlie P. Maths tutor

3837 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

What's the gradient of the curve y=x^3+2x^2 at the point where x=2?


Differentiate y=x^x with respect to x.


Find the inverse of the function g(x)=(4+3x)/(5-x)


In this question, take 'log' to mean 'log base 5'. Solve the equation log(x^2-5)-log(x) = 2*log(2)


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