Expand (3-x)^7

Question

Would i start like (3)^7(-x)0 etc....

Answer 1

Have you learned the binomial theroem?
If not, follow this pattern

(3-x)^7
= C(7,0) 3^7 (-x)^0 + C(7,1) 3^6 (-x)^1 + C(7,2) 3^5 (-x)^2 + .... + C(7,6) 3^1 (-x)^6 + C(7,7) 3^0 (-x)^7
= 1(3^7)(1) - 7(3^6)x + ... + 7(3)x^6 - x^7

You might also want to look into how Pascal's triangle works along with this topic.