If f(x) = 1/(6x^2), where x not equal to 0, find the rate of change when x=4.

f(x) can be rearranged to be: f(x) = 1/6 x-2This is then differentiated to be: f'(x) = -1/3 x-3 as the expression is multiplied by the original power (-2) and then the power is reduced by 1 (to -3)
f'(x) is then rearranged to be f'(x) = -1/(3x3) which x=4 can then be substituted into giving:
f'(4) = -1/(3*43) = -1/192

TR
Answered by Thomas R. Maths tutor

1414 Views

See similar Maths Scottish Highers tutors

Related Maths Scottish Highers answers

All answers ▸

y=x^3-3x^2+2x+5 a)Write down the coordinates of P the point where the curve crosses the x-axis. b)Determine the equation of the tangent to the curve at P. c)Find the coordinates of Q, the point where this tangent meets the curve again.


Differentiate 5x^2 - 7x +9


Show that (𝑥 − 1) is a factor of 𝑓(𝑥)=2𝑥^3 + 𝑥^2 − 8𝑥+ 5. Hence fully factorise 𝑓(𝑥) fully.


PQR is a triangle with vertices P (−2, 4), Q(4, 0) and R (3, 6). Find the equation of the median through R.


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