Integrate <span>f ''(x) = −2 + 36x − 12x2 with respect to x:
f '(x) = -2x + (36/2)x^2 - (12/3)x^3 + c. Find c by letting x = 0 and using f(0)=8.
Then f '(0) = -2x + 18x^2 - 4x^3 + c = 18 (which was given).
Then -0 + 0 - 0 + c = 18, so c = 18 and
f '(x) = </span>-2x + 18x^2 - 4x^3 + 18.
Go through the same integration process to find f(x).
Answer:
14 books
Step-by-step explanation:
Let b = number of books at the beginning
She sold 1/2 of the books
b - 1/2 b
This is how many she had left
Then she bought 7
b - 1/2 b + 7
this equals 14
b - 1/2 b + 7 = 14
Combine like terms
1/2 b + 7 = 14
Subtract 7 from each side
1/2 b = 14-7
1/2 b = 7
Multiply each side by 2
1/2 b * 2 = 7*2
b = 14
She started with 14 books
33% of 15 is 5. If 5 = 33%, that means that x/3=5. so multiply both sides by 3 to get x=15.
It is asking what number can you take 33% of and get 5? So you are not dividing 5 by 3, you are multiplying it by 3
