The extreme values of the function f(x) = x - 4sqrt(x) occur at the values of x for which f'(x) = 0
f'(x) = 1 - 2/sqrt(x) = 0
sqrt(x) - 2 = 0
sqrt(x) = 2
x = 4
To check for minimum or maximum,
f''(x) = 1/(sqrt(x))^3 = 1/(sqrt(4))^3 = 1/(2^3) = 1/8 => the point is a minimum.
Therefore, the minimum value = f(4) = 4 - 4sqrt(4) = 4 - 4(2) = 4 - 8 = -4 and occurs at x = 4.
Set up the equation of two ratios:
3 racks 36 racks
----------- = --------------
15 min x
Solve this for x: 3x =540; x = 180 minutes, or 3 hours
Answer:
100
Step-by-step explanation:
hope this helped :D
Answer:
8 1/2 miles
Step-by-step explanation:
Please use " ' " to indicate fractions:
Andrea rode her bike 3 2/3 miles on saturday and 4 5/6 miles on sunday.
Add together 3 2/3 and 4 5/6. The LCD is 6, so 3 2/3 should be rewritten as 3 4/6. Now 3 4/6 and 4 5/6 have the same denominator, 6.
3 4/6
+4 5/6
-----------
7 9/6. Note that 9/6 = 1 1/2, so rewrite
7 9/6 as 8 3/6, or 8 1/2.
She biked 8 1/2 miles in all.