Final answer:
Beta radiation, symbolized by the Greek letter ß, is emitted from the nucleus of radioactive elements such as tritium, carbon-14, and strontium-90.
Step-by-step explanation:
The type of radiation emitted from the nucleus of radioactive elements such as tritium, carbon-14, and strontium-90 is Beta radiation. Beta radiation consists of beta particles, which are high-energy electrons or positrons ejected from the nucleus. It is symbolized by the Greek letter ß.