Answer:
Yi Bangwon successfully defeated his brother's forces, then executed Bak Po and sent Yi Bang-gan into exile. King Jeongjong, who was afraid of his powerful brother, named Yi Bangwon as crown prince and abdicated in the same year. Yi Bangwon assumed the throne of Joseon at long last as King Taejong, the third king of Joseon.
Step-by-step explanation: