All circle and sphere equations are based on the radius, not the diameter.
Circumference is 2*r*pi, so with THAT you could use diameter. But for area, which is pi*r^2, no. Squaring a number and multiplying it by two aren't the same thing (except the case of the number 2)
No, you need one more part to the equation for it to give you area. This equation is : (pi d^2) / 4. Since a diameter is twice a radius, you need to divide out the doubled radius squared, or divide by 2^2 or 4. The simplest formula for finding the area of a circle will always be pi r^2. If a diameter is given , divide by 2 to get a radius, then use the simpler formula -- unless you like to be different.
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No.
All circle and sphere equations are based on the radius, not the diameter.
Circumference is 2*r*pi, so with THAT you could use diameter. But for area, which is pi*r^2, no. Squaring a number and multiplying it by two aren't the same thing (except the case of the number 2)
No, you need one more part to the equation for it to give you area. This equation is : (pi d^2) / 4. Since a diameter is twice a radius, you need to divide out the doubled radius squared, or divide by 2^2 or 4. The simplest formula for finding the area of a circle will always be pi r^2. If a diameter is given , divide by 2 to get a radius, then use the simpler formula -- unless you like to be different.
you can find the area of a circle using
A= pi * radius^2
the radius = 1/2 diameter
so substituting in
A = pi *(1/2 diameter)^2 = (pi * diameter^2)/4 so the equation you gave is wrong
The area = Ï r^2 = Ï (d/2)^2 = 1/4 Ï d^2
So yours R rong
area of a circle =Ï r^2 = Ï ( d/2)^2 = ( Ïd^2 ) / 4
no, that will get you 2x the circumference
(pi)r^2, or (pi)rr is the only way of finding the area
For a circle:
A=pi*r^2
2r=d ==> r=d/2
so
A=pi*(d/2)^2
A=(pi*d^2)/4
dϲ is not the area of a circle.
Try (d/2)Â²Ï or Ïr²
.
yes as the diameter is equal to two radii.
sorry to put it bluntly, but no xxx