Help with identifying the textbook

Recently I stumbled upon this topic - https://www.physicsforums.com/threads/simple-harmonic-motion-total-energy.736484/ and want to find out what textbook is in the photo. Any help would be greatly appreciated!

Welcome to PF.

That was 10 years ago.
Google "15.3 Energy in Simple Harmonic Motion"
Results in:
https://phys.libretexts.org/Bookshelves/University_Physics/University_Physics_(OpenStax)/Book:_University_Physics_I_-_Mechanics_Sound_Oscillations_and_Waves_(OpenStax)/15:_Oscillations/15.03:_Energy_in_Simple_Harmonic_Motion

Every freshman physics text should cover this topic.

Big thanks! I tried googling, though I didn't find the same book. Probably that's because current openstax University Physics is newer (published in 2016). Nevertheless, I am satisfied with the new version too