Mark M. answered 02/22/23
Retired math prof. Calc 1, 2 and AP Calculus tutoring experience.
Let y = x2/3 The point (64, 642/3) = (64, 16) is on the graph.
y' = (2/3)x-1/3 Slope of tangent at (64, 16) is (2/3)(64-1/3) = 1/6
Tangent line equation: y - 16 = (1/6)(x - 64)
So, y = 16 + (1/6)(x - 64)
(64.07)2/3 ≈ 16 + (1/6)(64.07 - 64) = 16.011666667