Odpowiedzi

2009-11-04T20:55:39+01:00
P=πr²
Ob=2πr

a)16π=2πr/:2π
r=8cm

P=πr²=π8²=64π
------------------------
π=2πr/:2π
r=1/2m

P=πr²=π(1/2)²=1/4πm²
----------------------------
0,12π=2πr/:2π
r=0,06mm

P=πr²=π(0,06)²0,036mm²
-----------------------------

4=2πr/:2π
r=4:2πdm

P=πr²=π(4:2π)²=16/4π²*π=4/πdm²
-----------------------------------------
2/3π=2πr/:2π
r=2/6=1/3km

P=πr²=π(1/3)²=1/9πkm²

b)
16π cm2=πr² /:π
16=r²
r=4cm
Obw=2πr
Obw=2π*4
Obw=8π cm
---------------------------
4/9πm2=πr² /:π
4/9=r²
r=2/3 m
Obw=2πr
Obw=2π*2/3
Obw=4/3πm
--------------------------
0,25πmm2=πr² /:π
0,25=r²
r=0,5mm
Obw=2πr
Obw=2π*0,5
Obw=π mm
----------------------------
2π dm2= πr² /:π
2=r²
r=√2dm
Obw=2πr
Obw=2π*√2
Obw=2√2πdm
---------------------------------------
3 km2=πr² /:π
3/π=r²
r=√3/π km
Obw=2πr
Obw=2π*√3/π
Obw=2√3π km
2009-11-04T21:02:37+01:00
A)
2πr = 16π
r=8 cm
P =π r² =64π cm²

2πr = π
r=1/2 m
P=1/4π m²

2πr = 0,12π
r=0,06 mm
P=0,0036π mm²

2πr = 2/3*π
r=1/3 km
P= 1/9π km²

2πr = 4
r=2/π dm
P= 4/π fm²


b)
πr²=16π cm²
r=4
Obw = 8π cm

πr²=4/9π m²
r=2/3
Obw = 4π/3 m

πr²=0,25π mm²
r=0,5
Obw = π mm

πr²=2 π dm ²
r=√2
Obw = 2√2 π dm

πr²= 3 km ²
r=√3
Obw = 2√3 π km


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