Question

#10 and #12

8. Find all points (.y) where fCx.y) -3x2 + 7xy -4y2 + x + y has possible relative maximum or minimum values 9. Find all points (x,y, z) where f(x,y,z) 5+ 8x 4y+x2+y2 z2has possible relativema imun or minimum value 10. Both first partial derivatives of f(x.y)-x-4xyy are zero at the points (0 11. Find all points (x,y) where f(e.y) 2x2+3xy + 5y has possible relative maximum or minimum values. Then, use the 12. Use the second 13. A monopolist manufactures and sells two competing products, I and II, that 0), (1,1), and (-1,-1). Use the second ven points. derivative test (for multivariable functions) to determine the nature of f(x, y) at each of these g If the second-derivative test is inconclusive, explain why area that has a volume of 1000 cubic inches. produce. The revenue from marketing x units of product I and y units of produt II is values of x and y that maximize the monopolist's profits derivative test (for multivariable functions) to determine, if possible, the nature of f (x. y) at each of thes d-derivative test (for multivariable functions) to find the dimensions of the rectangular box of least surface cost $30 and $2 0 per unit, respectively, to 0.1x2 -0.04xy- 0.2y2. Use the second-derivative test (for multivariable functions) to find the

Answer 1

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