⇒ | πr^{2}Θ | = 72π |
360° |
∴ Θ = | 72π × 360° |
πr^{2} |
= | 72 × 360° | = 20° |
36 × 36 |
Now, length of arc = | πrΘ |
180° |
= | π × 36 × 20° | = 4π cm |
180° |
1 | (diagonal)^{2} = | 1 | × (2a)^{2} = 2a^{2} | |
2 | 2 |
π(3)^{2} | |
2 |
∴ x = | 9π | cm^{2} |
2 |
π(4)^{2} | |
2 |
∴ y = | 16π | cm^{2} |
2 |
π(5)^{2} | |
2 |
∴ z = | 25π | cm^{2} |
2 |
( | 9π | + | 16π | ) | – | 25π | = 0 | |
2 | 2 | 2 |
= πr^{2} : | 1 | × 2r × r = π |
2 |