I'm trying to get an intuitive sense for errors and picked some random numbers:(adsbygoogle = window.adsbygoogle || []).push({});

x = 2.5 +/- 0.01

find f(x) = x³

d f(x) / dx = 3x²

d f(x) = 3x² dx

= 3(2.5)² 0.01

= 0.1875

What I don't get is why f(x - Δx) ≠ f(x) - 0.1875 and why f(x + Δx) ≠ f(x) + 0.1875

Where did I go wrong in my method for finding the uncertainty value? Thanks

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Propagation of Error/Uncertainty

**Physics Forums | Science Articles, Homework Help, Discussion**