- (a) At (−1,8), so the tangent line is
y − 8 = 5(x − (−1)). Therefore f (x) ≈ 8 + 5(x + 1).
(b) f (3) ≈ 8 + 5(0 + 1) = 13.
(c) At (−1,8), For Δx = 0.5, Δy = 0.5(5) = 2.5, so move to
(−1 + 0.5, 8 + 2.5) = (−0.5,10.5).
At (−0.5,10.5), For Δx = 0.5, Δy = 0.5(8) = 4, so move to (−0.5 + 0.5,
10.5 + 4).
Thus f (0) ≈ 14.5.