Do Brahma, Vishnu and Mahesh also die according to Vedas?

NO Lord Brahma, Lord Vishnu and Lord Shiva DO NOT die. The eternal Lord Shiva (Shiva Tattva) resides eternally in the eternal Kailash (Mahesh Dhama). The eternal Lord Vishnu (Vishnu Tattva) resides in the eternal Vaikuntha (Hari Dhama). read more

Anything that can be imagined, perceived, grasped , explained are limited. The infinite can never be really understood , explained, perceived by mortal human beings. That which is aprameya [beyond explanation] is Parabrahman. The concept of Shiva, Vishnu, Brahma or any other God as the supreme Brahman is limited. read more

If you refer to Yog Vasistha you will find sage Vasistha saying that even Gods like Vishnu and Mahesh are not immortal which means they also die. Also Vishnu and Mahesh are born at the creation of universe strongly suggesting that they die too because who is born also dies. read more