Compute f '(a) algebraically for the given value of a. HINT [See Example 1.]

Question

f(x) = −6x − x2; a = 4

Answer 1

F(x)= - X^2 - 6X. a = 4.
F'(x) = - 2X - 6,
F'(a) = - 2a - 6, a = 4.
F'(4) = -2*4 - 6 = -14.