WOLFRAM
|
DEMONSTRATIONS PROJECT
Area of a Disk
o
p
e
n
i
n
g
T
h
e
a
r
e
a
o
f
a
d
i
s
k
w
i
t
h
r
a
d
i
u
s
R
i
s
1
2
(
2
π
R
)
R
=
π
2
R
.