Use Pascal's triangle to expand (a+b)^6 and hence find the binomial expansion of: (x-3)^6

Answer 1

I can not do the symmetry with keyboard
remember rows and columns start wit 0, so we need 7 rows
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 1
1 6 15 20 15 6 1 ah ha
so
a^6 + 6 a^5 b + 15 a^4 b^2 + 20 a^3 b^3 + 15 a^2 b^4 + 6 a b^5 + b^6

Answer 2

I hope it was right