Question

“Find the critical values at which each of the following cubic functions is optimized and test the second-order conditions to see if the function is at a relative maximum, relative minimum, inflection point, or saddle point.

“(c) z = 8x^2 − 6y^3 + 144xy − 323
(d) z = 6x^3 + 6y^3 + 54xy − 195”

ans((c) (0, 0), inflection point; (648, −72), relative minimum
(d) (0, 0), inflection point; (−3, −3), relative maximum) show process

Answer 1