If f(-2)=1 and f'(-2)=5, what is the approximate value of f(-2.01)?

2 Answers
Dec 29, 2016

f(-2.01) ~~ 1.05f(2.01)1.05

Explanation:

Assuming that f(x)f(x) is differentiable in the neighborhood of x=2x=2, from the Second Fundamental Theorem of Calculus,

f(-2.01) = f(-2) + int_{-2}^{-2.01} f'(x) "d"x

Using a right rectangle approximation, assume that f'(x) ~~ f'(-2) for all -2.01 <= x <= -2

The above equation then becomes

f(-2.01) ~~ f(-2) + int_{-2}^{-2.01} f'(-2) "d"x

= f(-2) + [-2-(-2.01)] f'(-2)

= f(-2) + [-2-(-2.01)] (5)

= f(-2) + (0.01) (5)

= f(-2) + 0.05

= 1 + 0.05

= 1.05

Dec 30, 2016

0.95

Explanation:

f(x+h)approx f(x)+hf'(x)
Let h=-0.01, x=-2, f(x)=1, f'(x)=5

f(-2-0.01)approx (1)+(-0.01)xx(5)
f(-2.01)approx 0.95