If (3+x2020+x2021)2022=a0+a1x+a2x2+⋯+a10xn, then the value of a0−12a1−12a2+a3−12a4−12a5+a6⋯ is (correct answer + 2, wrong answer - 0.50)
If (1+x+x2)n=a0+a1x+a2x2+....+a2nx2n, then a0+a3+a6+.....=