greetings,

following books are best for gate preparation:

• strength of materials by ss rattan
• theory of machines by rs khurmi
• network analysis van Valken
• engieneering mathematics by bs grewal

pls read/revise all the books that you read during btech.

pls specify your branch for more information.

following is the link for more information about gate:

https://engineering.careers360.com/exams/gate

hope this helps.

good luck