if the perimeter of the window is 32 feet, find the exact value of x (in ft) so that the greatest possible amount of light is admitted.



Answer :

The exact value of x is 4.48 ft so that greatest possible amount of light is admitted .

Norman window shap is rectangular surrounding by semi circle .

let x be the width and h be the height of window.

Therefore, radius of semi- circle is x/2 .

we have given that

perimeter of the window = 32 ft

the perimeter of semi-circle = π × x/2

the perimeter of rectangular = 2h + x

perimeter of window ( rectangular surrounding by semi circle) = 2h + x + πx/2 = 32 ---(1)

Area of rectangular part = x × h

Area of semi circle= π×(x/2)²

Area of window = π×(x²)/4 + xh ---(2)

Now, we must maximize the area of window so that greatest amount of light admitted.

using (1) , h = 16 - x/2 - πx/4

Area of window (A) = πx²/4 + 16x - x²/2 - πx²/4

A = 16x - x²----(3)

for maximize we take first order derivative of area and then put it equal to the zero for finding the critical value of x .

differentating equation (3) with respect to x we get, dA/dx = 16 - 2x

now, dA/dx = 0 so, 16 - 2x = 0 => x= 8

Hence , the exact value of x is 8 .

To learn more about Maximize problem , refer :

https://brainly.com/question/19819849

#SPJ4

Complete question:

Norman window has the shape of rectangle surmounted by semicircle: (Thus the diameter of the semicircle equal to the width of the rectangle labeled x. ) If the perimeter of the window Is 32 feet, find the exact value of x (In ft) so that the greatest possible amount of Iight Is admitted

View image contexto1024