First of all, when I do all the math on this, I get the coordinates for the max point to be (1/3, 14/27). But anyway, we need to find the derivative to see where those values fall in a table of intervals where the function is increasing or decreasing. The first derivative of the function is
. Set the derivative equal to 0 and factor to find the critical numbers.
, so x = -3 and x = 1/3. We set up a table of intervals using those critical numbers, test a value within each interval, and the resulting sign, positive or negative, tells us where the function is increasing or decreasing. From there we will look at our points to determine which fall into the "decreasing" category. Our intervals will be -∞<x<-3, -3<x<1/3, 1/3<x<∞. In the first interval test -4. f'(-4)=-13; therefore, the function is decreasing on this interval. In the second interval test 0. f'(0)=3; therefore, the function is increasing on this interval. In the third interval test 1. f'(1)=-8; therefore, the function is decreasing on this interval. In order to determine where our points in question fall, look to the x value. The ones that fall into the "decreasing" category are (2, -18), (1, -2), and (-4, -12). The point (-3, -18) is already a min value.
The rule of 72 will have you divide 72 over the interest rate in percent form. Ignore the percent symbol
So we'll divide 72 over 8.47 to get...
72/8.47 = 8.50059
which is roughly 8.5 years for the money to double
If we round to the nearest whole number, then it takes 9 years for the money to double (according to the rule of 72). The year 1999 isn't listed so the next best choice is the year 2000. So I'm fairly confident the answer is C) 2000. Though your teacher may have 1998 in mind for some reason. If it were me, I'd go with 2000 because the year 1998 will have the account balance short of the goal of $10,000.
Answer: Choice C) 2000
Answer:
Hello! answer: -6
4 ÷ 2 = 2 5 - 8 = -3
2(-3) = -6 therefore the answer is -6 hope that helps!
Answer:
66 = s
Step-by-step explanation:
s + 24 = 90
90 = s + 24
90 - 24 = s
66 = s