Question

Aflați aria discului cu raza de: A)8 pe π ( cm) B)14 cm C)1 pe 20(m) Va rog mult!!!!

Answer 1

a) $A_{disc}= \pi R^{2} \\ R= \frac{8}{ \pi} =\ \textgreater \ A_{disc}= \pi *( \frac{8}{ \pi} )^{2} = \pi * \frac{64}{ \pi ^{2}} = \frac{64}{ \pi } cm^{2}$

b) $A_{disc}= \pi R^{2} \\ R=14cm=\ \textgreater \ A_{disc}= \pi *14^{2} = 196 \pi cm^{2}$

c) $A_{disc}= \pi R^{2} \\ R= \frac{1}{20} m =\ \textgreater \ A_{disc}= \pi *( \frac{1}{20} )^{2} = \pi * \frac{1}{400} = \frac{ \pi }{400} \ m^{2}$