ForA=2x^2 –18x+80 (i) find dA/dx , (ii) find the value of x for which A is a minimum

dA/dx = 4x -18 : multiply the number before the x (coefficient) by the power and minus 1 from the power.4x = 18 so x = 4.5 to find the minimum or maximum point, make the differential equal to 0 and solve for x.In order to check if it is a minimum point differentiate the equation again ( dA^2/d^2x = 4) - 4 > 0 and therefore it is a minimum point.

Answered by Dan A. Maths tutor

4899 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the following simultaneous equations. x^2+y^2=25. y-3x=13


Expand and simplify 3(x+4) - 2(4x+1)


Solve the equation "3y + 5 = 11" to find the value of y.


Solve the simultaneous equations 3x + y = –4 and 3x – 4y = 6


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 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences