F(x) = 18-x^2 is a parabola having vertex at (0, 18) and opening downwards.
g(x) = 2x^2-9 is a parabola having vertex at (0, -9) and opening upwards.
By symmetry, let the x-coordinates of the vertices of rectangle be x and -x => its width is 2x.
Height of the rectangle is y1 + y2, where y1 is the y-coordinate of the vertex on the parabola f and y2 is that of g.
=> Area, A
= 2x (y1 - y2)
= 2x (18 - x^2 - 2x^2 + 9)
= 2x (27 - 3x^2)
= 54x - 6x^3
For area to be maximum, dA/dx = 0 and d²A/dx² < 0
=> 54 - 18x^2 = 0
=> x = √3 (note: x = - √3 gives the x-coordinate of vertex in second and third quadrants)
d²A/dx² = - 36x < 0 for x = √3
=> maximum area
= 54(√3) - 6(√3)^3
= 54√3 - 18√3
= 36√3.
(100^5) * 4000 = 10000000000 * 4000 = <span>4 * 10^13</span>
Answer:
use pythagorean theorem
Step-by-step explanation:
a^2+b^2=c^2
Answer:

Step-by-step explanation:
the volume of a cylinder is given by:

and the volume of a cone is given by:

since both have the same height and radius, we can solve each equation for
(because this quantity is the same in both figures) and then match the expressions we find:
from the cylinder's volume formula:

and from the cone's volume formula:

matching the two previous expressions:

we solve for the volume of a cone
:

substituting the value of the cylinder's volume 
