Question 1
Find the value of y" at
given that x
3 y + xy
2 = 6.
◦
◦
◦
◦ -1
◦ 3
Question 2
Find the points at which the curve 5x
2 + 6xy + 5y
2 = 80 has horizontal tangent lines.
◦ (3, 5), (3, -5), (-3, 5), and (-3, -5)
◦ (3, 5), (5, -3), (-3, 5), and (-5, -3)
◦ (3, -5) and (-3, 5)
◦ (5, -3) and (-5, 3)
◦ The curve does not have horizontal tangent lines.