Finding the uncertainty in delta y?

[SJay16]

Homework Statement

Find the uncertainty ∆y in y as a function of the uncertainties ∆u and ∆v in u and v for the following functions:
y = 1/2(u+v)

Homework Equations

:
Error propagation formula[/B]

The Attempt at a Solution

Don't know where to begin even. Help?[/B]

 

[Marc Rindermann]

try partial differentiation $\Delta y = |\frac{\partial y}{\partial u}|\Delta u + |\frac{\partial y}{\partial v}|\Delta v$

 

[haruspex]

Homework Statement

Find the uncertainty ∆y in y as a function of the uncertainties ∆u and ∆v in u and v for the following functions:
y = 1/2(u+v)

Homework Equations

:
Error propagation formula[/B]

The Attempt at a Solution

Don't know where to begin even. Help?[/B]

Please quote the error propagation formula as you understand it.