https://electricalstudent.com/3-28-for-a-particular-junction-for-which-cj0-0-4-pf-v0-0-75-v-and-m-1-3-find-cj-at-reverse-bias-voltages-of-1-v-and-3-v-0-23-pf/
3.28 For a particular junction for which Cj0 = 0.4 pF, V0 = 0.75 V, and m = 1/3, find Cj at reverse-bias voltages of 1 V and 3 V. 0.23 pF