Let f be a function such that f(1)= 2. At each point (x, y) on the graph of f, the slope is given by dy = 5.xy – x - y - 5. Which of the following statements is true? dx %3D
a. f has a relative minimum at x = 1.
b. f has a relative maximum at x = 1.
c. f has neither a relative minimum nor a relative maximum at x = 1.
d. There is insufficient information to determine whether f has a relative minimum, maximum, or neither at x = 1.
