Find the intervals on which the function f(x) = ax2 + bx + c (where "a" doesn't = 0) is increasing and decreasing. Describe the reasoning behind your answer.

Step-by-step explanation:

Given that:

The derivative of the function of x is  

Thus; f(x) is increasing when f'(x) > 0

f(x) is decreasing when f'(x) < 0

i.e

f'(x) > 0 , when  b > 0  and a < 0

∴

2ax + b < 0

2ax < - b

f'(x) < 0 , when  b < 0  and a > 0

2ax + b > 0

2ax > - b

the best buy, is the 4- kilogram bag of lollipops for $18.40.

step-by-step explanation:

i found my answer by dividing the cost of each bag by their respective weights.

14.88 divided by 2 = 7.44

17.29 divided by 3 = 5.77

18.4 divided by 4 = 4.6

24.4 divided by 5 = 4.88

by this, i found that the 4 kilo bag is the best buy.

it is b)

hope this : )

step-by-step explanation: