# The value Of a Voltage Can someone help

So i was working on JFET networks and in the calculation of The output impedance (Solution from the book) I am stuck in the solution My question is How can Vrd = V0 + Vgs ?

• It looks like the condition for IDSS with Vi=0 and that hilite looks incorrect. Dec 30 '17 at 20:47
• No it's correct Vi - Vgs = V0-Vrd Dec 30 '17 at 21:11
• ok and it applies when Vi=0 such that $V_{r_d}=V_o+V_{gs}$ Dec 30 '17 at 21:41