Here's the question you clicked on:
chaand.i
iP={P⋅v3/2PK0if vPK>0if vPK<0 What is the incremental resistance (in Ohms) for the bias voltage of VPK=7.0V? What is the incremental resistance (in Ohms) for the bias voltage of VPK=15.0V?
you must find the derivative of: \[(Ip/p)^{2/3}\] you should get... \[\frac{ 2(\frac{ Ip }{ p })^{2/3} }{ 3(Ip) }\] this essentially gives u ur answers... but make sure to convert your mA to A