Answer:

Step-by-step explanation:
the minimum of f is for x = 1 and f(1)=0
f is decreasing for x<=1 and increasing for x>=1
so the domain is 

x>=1 so x is positive and we can take the square root
so 
A = LW
A = 2/3 * 3/4
A = 6/12 = 1/2 miles^2
So there is an identity we'll need to use to solve this:
cos(x+y) = cosxcosy - sinxsiny
replace the numerator with the right hand side of that identity and we get:
(cosxcosy - sinxsiny)/cosxsiny
Separate the numerator into 2 fractions and we get:
cosxcosycosxsiny- sinxsiny/cosxsiny
the cosx's cancel on the left fraction, the siny's cancel on the right fraction and we're left with:
cosy/siny - sinx/cosx
which simplifies to:
coty - tanx
67-x-20 hope this helped!!
Answer:
0.22 per
Step-by-step explanation: