A rain gutter is to be constructed of aluminum sheets 12 inches wide. After marking off a length of 4 inches from each edge, this length is bent up at an angle θ. The area A of the opening may be expressed as the function: A(θ) = 16 sin θ ⋅ (cos θ + 1). If θ = 90°, what is the area of the opening?
We are already given with the function to solve for the area:
A(θ) = 16 sin θ ⋅ (cos θ + 1)
We simply have to substitute the value of the angle into the function. So,
If θ = 90°,
A(90°) = 16 sin (90°) ( cos (90°) + 1 )
Using the calculator or the definition of trigonometric functions at angle of 90°, we get the value of the area:
A(90°) = 16 square inches
we know that
The area A of the opening may be expressed as the function:
\(A(\alpha) = 16 sin \alpha* (cos \alpha + 1)\)
For \(\alpha =90\)°
We simply have to substitute the value of the angle into the function
so
\(A(90) = 16*sin 90* (cos 90 + 1)\)
\(A(90) = 16*(1)* (0 + 1)\)
\(A(90) = 16 in^{2}\)
therefore
the answer is
the area of the opening is \(16 in^{2}\)