If the radius is R and the square sector area is s, then the square of n is ()

If the radius is R and the square sector area is s, then the square of n is ()

Because s = 1 / 2 * NR * r = NR ^ 2 / 2
So n = 2S / R ^ 2
We can see that n ^ 2 = 4S ^ 2 / R ^ 4

Why n / 360 = R / L?
Why sector and circle n / 360 = R / L?

S sector = NR squared / 360
=(n∏R/180)*R/2
Because l = n Π R / 180
So s sector = 2 / 1 L R

Cut a circle into an approximate rectangle. The circumference of the rectangle is 8.28cm. Calculate the area of the circle

2*3.14*r+2r=8.28
8.28r=8.28
r=1
Area 3.14 * 1 * 1 = 3.14 square centimeter

Divide a circle into several equal parts to form an approximate rectangle. If the circumference of the rectangle is 41.4cm, the circumference of the circle is______ The area is______ ．

The radius of the radius of the circle is x centimeter, which is the radius of the radius of the circle is x centimeter, which is the radius of the radius of the radius of the circle is x centimetre. & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 3.14 × 2x2x2x + 2x = 41.4, and 2x2x2x (3.14 + 3.14 + 1) (41.4, 41.4, and 2x2x2x (3.14 + 3.14 + 1) (3.14 + 3.14 + 3.14 + 1) (41.4, 41.4, 41.4, 41.4, 41.4, 4, 41.4, and 41.4, 41.4, 41.4, 41.4, 4, 41.4, 41.4, 4, and 41.4, 41.4, 41.4, 41.4, 41.4, 41.4, and 41.4, 41.4, 41.4, and 41.4, 41.4, and 41.4, 41.4, 41.sp; & nbsp; X = 5; circumference of the circle: 3.14 × 5 × 2, = 3.14 × 10, = 31.4 (CM); area of the circle: 3.14 × 52, = 3.14 × 25, = 78.5 (square cm). Answer: circumference of the circle is 31.4 cm; area is 78.5 square cm