Real part of (cos‌4+i‌sin‌4+1)2020= Real part of (2‌cos22+i‌2‌sin‌2‌cos‌2)2020 = Real part of 22020cos2020(2)(cos‌2+i‌sin‌2)2020 = Real part of 22020cos2020(2)(cos‌4040+i‌sin‌4040) =22020cos20202.cos‌4040[z+z=2‌Re(z)]