Let's check.
x = 5π/24
4x = 5π/6
cos 4x = cos(5π/6) = cos 150° = -√3/2
cos² 4x = (-√3/2)^2 = 3/4
4 cos² 4x -3 = 4 (3/4) - 3 = 0
Answer: TRUE
Answer:
Pedro got 1520 base hits and Ricky got 1243.
Step-by-step explanation:
This question can be solved by a system of equations.
I am going to say that:
x is the number of base hits that Pedro got.
y is the number of base hits that Ricky got.
Pedro and Ricky got 2673 base hits last season.
This means that 
Pedro had 277 more hits than Ricky.
This means that 
Replacing in the first equation






Pedro got 1520 base hits and Ricky got 1243.
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.
Answer:
your work is not clearly taking sorry i can't see