He spent exactly 20.25, so it's A.
Basically you just divide:
123/3 = 41
So the sale price of the coat would be $41
When x = 1:
1³ + 1 - 3 = -1
When x = 2:
2³ + 2 - 3 = 7
Since f(x) = x³ + x - 3 is continuous, it follows from the intermediate value theorem that for some c in the interval (1, 2), we have f(c) = 0, since f(1) < 0 < f(2).
