Basic Math Examples

Find the Circumference circle (5cm)
r=5cmr=5cm
Step 1
The circumference of a circle is equal to Pi ππ times the diameter dd.
π(diameter)π(diameter)
Step 2
Since the diameter dd is equal to 22 times the radius rr, the formula for circumference using radius is 2πr2πr.
2π(radius)2π(radius)
Step 3
Substitute the value of the radius r=5r=5 into the formula for the area of a circle. Pi ππ is approximately equal to 3.143.14.
2π52π5
Step 4
Multiply 55 by 22.
10πcm10πcm
 [x2  12  π  xdx ]  x2  12  π  xdx