A curve has equation x^2 +2xy–3y^2 +16=0. Find the coordinates of the points on the curve where dy/dx = 0.

x2 +2xy–3y2+16=0Differentiate the terms:x2 gives 2x2xy is differentiated by the product rule: vu' +v'u Make v = 2x and u = y, which gives 2x(dy/dx) + 2y3y2 gives 6y(dy/dx)16 gives 0.Therefore we have the equation: 2x + 2x(dy/dx) + 2y - 6y(dy/dx) = 0Now collect like terms: 6y(dy/dx) - 2x(dy/dx) = 2x + 2yFactor out dy/dx: dy/dx = (2x+2y)/(6y-2x)The question asks for points where dy/dx = 0, so substituting this in gives: 0 = (2x+2y)/(6y-2x) 0 = 2x + 2y y = -xNow to find the points on the curve where dy/dx is 0, we know y=-x and so substituting this into the original equation gives: x2 + 2x(-x) - 3(-x)2 + 16 = 0 x2 - 2x2 - 3x2 + 16 = 0 4x2 = 16 x2 = 4 x = (+/-) 2 Therefore y = (-/+) 2And now we have our answer, the coordinates are (2,-2) and (-2,2)

DA
Answered by Dilan A. Maths tutor

11496 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Differentiate x^5 + 3x^2 - 17 with respect to x


Prove by contradiction that sqrt(3) is irrational. (5 marks)


Find the gradient of the line Y = X^3 + X + 6 when X = 4


A block of mass M lies stationary on a rough plane inclined at an angle x to the horizontal. Find a general expression relating the coeffecient of friction between the block and the plane and the angle x. At what angle does the box begin to slide?


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