Find the partial diameter error of the surface area of cylinder

[abobik]

Homework Statement

Hello everyone. I need help.
How Can I find partial diameter error of surface area of cylinder if I have diameter absolute error, average diameter and average height. Just write a formula. Please!

Relevant Equations

Using derivative

(ΔSA/ΔD) = 2πHΔD
Something is wrong I guess as I get wrong value.

 

[Cutter Ketch]

You didn’t do the derivative correctly. Write the formula more carefully and then take the derivative more carefully. Hint: D is not $\Delta D$ (but also careful with the constants)

 

[abobik]

You didn’t do the derivative correctly. Write the formula more carefully and then take the derivative more carefully. Hint: D is not $\Delta D$ (but also careful with the constants)

Thanks! But, actually, I don't really get it.. Now, the formula is Partial Diameter Error = (2πH + πD) * ΔD?

 

[haruspex]

Thanks! But, actually, I don't really get it.. Now, the formula is Partial Diameter Error = (2πH + πD) * ΔD?

Start by posting the formula you are using for the area.