<img width="916" height="422" alt="Image" src="https://github.com/user-attachments/assets/fc47d443-c441-4034-92f4-8cbd66741d9d" /> 1) ua error 8-24 defines a substitution. 8-25 incorrectly applies it. It should be ua, not {ua,uo}^T 2) The G_mn^T should be G_oa^T <img width="925" height="207" alt="Image" src="https://github.com/user-attachments/assets/6abc139f-d2c9-4ff3-aae0-2ff2d4ec55b9" /> 3) 8-26 repeats substitution error with Ua,Uo on both the mass and stiffness terms
8-24 defines a substitution.
8-25 incorrectly applies it. It should be ua, not {ua,uo}^T