Since we're trying to estimate *f'*(1.2), that means we're using *a* = 1.2: The table gives us *f*(*a* + *h*) for *h* = -0.2, -0.1, 0.1, 0.2. That's not great, but we've got to use what we've got. We can rearrange the information we're given into a table that looks like the ones we've been using: Then all that remains is to calculate the slopes: As *h* approaches 0 from the right, we find slopes of 5 and 5. As *h* approaches 0 from the right, we find slopes of 3.5 and 4. It looks like *f'*(1.2) is somewhere in between 4 and 5. |