5 Consider the function f(x, y) = x¹ − x² + y² + 2xy +1

(a) There is a stationary point at the origin; Find the location(s) of any

other stationary points.

[3 marks]

[2 marks]

(b) Find the nature of the stationary point at the origin.

(c) Along the curve y = x², for positive x, what is the minimum value of

the function f(x,y) ?

[3 marks]