Given y=x^3+5x+3 find dy/dx when x=3

The question can be broken into two steps, 

1) dy/dx is asking to differentiate y=x3+5x+3 with respect to x

Differentiating we multiply by the current power and lower this powers value by 1. ( Constants differentiate to nothing )

i.e  x3 goes to 3x2

dy/dx=  3x2+5

2) Next we need to find the value of dy/dx when x=3 done simply by substituting all x's in the equation by 3

dy/dx=  3*(3)+ 5 = 32

RL
Answered by Robert L. Maths tutor

11868 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Sue has 2 cats. Each cat eats 1 4 of a tin of cat food each day. Sue buys 8 tins of cat food. Has Sue bought enough cat food to feed her 2 cats for 14 days? You must show how you get your answer.


Find values for x and y from two simultaneous equations: 2x + y = 5 and 3x + y = 7


Factorise fully 12x^2-20x+3


How do you expand Double Brackets?


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