The circumference formula is 2 times pi times radius. In this case, we are substituting pi with 3.14. So, 3.14 times 2 times 4 (the radius) = 25.12. Therefore, the circumference is 25.12 m.
The formula for the area of a circle is pi times radius squared.
4^2 = 16.
16 times 3.14 = 50.24
So, the area of the circle is 50.24 squared, or 50.24^2.
Special cases of the sum and difference formulas for sine and cosine yields what is known as the double‐angle identities and the half‐angle identities.
