The parametric equations for x and y describe a circle of radius 10 m, so the length of the base of the fence is the length of the circumference of a circle of radius 10 m. The formula for that circumference (C) is ...
... C = 2πr
... C = 2π·(10 m) = 20π m
The height as a function of angle (t) is found by substituting for x and y.
... h(t) = h(x(t), y(t)) = 4 + 0.01·((10cos(t))²-)10sin(t))²) = 4+cos(2t)
The average value of this over the range 0 ≤ t ≤ 2π is 4, since the cosine function has two full cycles in that range, and its average value over a cycle is zero.
Thus, the area of one side of the fence is that of a rectangle 20π m long and 4 m wide. That will be
... (20π m)·(4 m) = 80π m²
The amount of paint required to cover both sides of the fence is
... 2×(80π m²)×(1 L)/(10 m²) = 16π L ≈ 50.3 L
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You can work out the integral for area as a function of t. When you do, you will find it gives this same result.
Answer:

Step-by-step explanation:
we know that
The roots of the polynomial are the values of x when the value of the polynomial f(x) is equal to zero
The roots of the polynomial function are
x=-6 -----> (x+6)=0
x=-5 -----> (x+5)=0
x=-1 -----> (x+1)=0
The equation of the cubic polynomial is

where
a is the leading coefficient
Remember that
f(0)=60
That means ------> For x=0 the value of f(x) is equal to 60
substitute the value of x and the value of y in the function and solve for a




so

Applying the distributive property
Convert to expanded form

LHS: =

(using

)
We know

so we can replace the sin²x in the LHS expression as follows

which is the RHS.