# Tag Info

Lets assume that you measure $a$ and $b$ with error that has a standard deviation of $\sigma_a,\sigma_b$, respectively. We can model your measurements as $\hat a = a+\epsilon_a,\hat b = b+\epsilon_b$, where $Var(\epsilon_a)=\sigma_a^2,Var(\epsilon_b)=\sigma_b^2$ and $E[\epsilon_a]=E[\epsilon_b]=0$. Then, we can write $\hat c = f(\hat a, \hat b)$. Now, ...