Нужна помощь, 49/7b-b^2-7/b,при b=-3

Question

Нужна помощь, 49/7b-b^2-7/b,при b=-3

Answer 1

49/7b - b^2 - 7/b = 49/7b - 7b^3/7b - 49/7b = - 7b^3/7b = -b^2
b=-3
-b^2 = -(-3)^2 = 3^2 = 9

Answer 2

49\7b - b²-7\b=7\b - b²-7\b = (7-b²-7)\b =-b²\b = -b

Comments

пасиб)