Let f(x) = \sqrt[3] x. The equation of the tangent line to f(x) at x = 125 is

y =
Using this, we find our approximation for \sqrt[3] {125.4} is =

1 answer

apparently you mean

f(x) = ∛x
f(125) = 5

f'(x) = 1/3∛x^2
f'(125) = 1/75

So, now you have a point and a slope. The line is

y-5 = 1/75 (x-125)