Given that f(x)= (3+x^2)(x^1/2-7x). Find f'(x) (5marks)

Because there are two functions that are enclosed in brackets, you should realise that you need to differentiate by parts. You can expand out and differentiate through, but because of the x^1/2 it can get quite complicated and messy. Step 1. define f(x) and g(x)h(x)=3+x^2 g(x)=x^1/2-7xNow differentiate both of those separatelyh'(x)=2xg'(x)=1/2x^-1/2x-7It is worthwhile writing the formulaf'(x)=h'(x)g(x)+h(x)g'(x)substitute into the formulatef'(x)=2x(x^1/2-7x)+(3+x^2)(1/2x^-1/2-7)

AS
Answered by Amrit S. Maths tutor

3352 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Express 3sinx - 2cosx in the form R(sin(x-a) given R>0 and 0<a<90°. Hence solve 3sinx - 2cosx = 1 in the interval 0<x<360°. What are the maximum and minimum values of 2sinx - 3cosx?


The curve C has equation (4x^2-y^3+3^2x)=0. The point P (0,1) lies on C: what is the value of dy/dx at P?


A stone was thrown with velocity 20m/s at an angle of 30 degrees from a height h. The stone moves under gravity freely and reaches the floor 5s after thrown. a) Find H, b)the horizontal distance covered


(1.) f(x)=x^3+3x^2-2x+15. (a.) find the differential of f(x) (b.) hence find the gradient of f(x) when x=6 (c.) is f(x) increasing or decreasing at this point?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences