# Uncertainty homework help

1. Nov 25, 2008

### lemaire

1. The problem statement, all variables and given/known data

I know Theta1 and Theta2. I also know sin(Theta1) and sin(Theta2). I am being asked to find the uncertainty of sin(Theta1) and sin(Theta2).

2. Relevant equations

3. The attempt at a solution
Should i use the error propagation rule here? if so, will the uncertainty of sin(Theta1) be the partial derivative of sin(Theta1) with respect to Theta thus be cos(Theta1)?

2. Nov 26, 2008

### gabbagabbahey

Re: uncertainty

You can use the propagation rule; but you also need to know the error in theta $\Delta \theta_1$ and $\Delta \theta_2$....and don't forget to include absolute value signs around your partial derivatives, since absolute error is typically expressed as a positive number.