Kopertina e librit Matematika 10 - 11: Pjesa I

Zgjidhja e ushtrimit 5

Zgjidhja e ushtrimit 5 të mësimit 11.1A në librin Matematika 10 - 11: Pjesa I nga shtëpia botuese Botime Pegi me autorë Steve Fearnley, June Haighton, Steve Lomax, Peter Mullarkey, James Nicholson dhe Matt Nixon.


Pyetja

Kopjoni dhe plotësoni tabelën e mëposhtme.

Zgjidhja

  1. r=6r=6 cm; d=2r=2×6=12d=2r=2\times 6 = 12 cm; P=2πr=2×π×6=12π37.7P=2\pi r = 2\times \pi \times 6 = 12\pi \approx 37.7 cm; S=πr2=π×62=36π113.1S=\pi r^2 = \pi \times 6^2 = 36\pi \approx 113.1 m2.
  2. r=d2=4.62=2.3r=\dfrac{d}{2}=\dfrac{4.6}{2}=2.3 m; d=4.6d=4.6 m; P=2πr=2×π×2.3=4.6π14.5P=2\pi r = 2 \times \pi \times 2.3 = 4.6\pi \approx 14.5 m; S=πr2=π×2.32=5.29π16.6S=\pi r^2 = \pi \times 2.3^2 = 5.29\pi \approx 16.6 m2.
  3. P=2πr98=2πrr=982π15.6P=2\pi r \rArr 98=2\pi r \rArr r=\dfrac{98}{2\pi} \approx 15.6 mm; d=2r=2×15.6=31.2d=2r = 2 \times 15.6 = 31.2 mm; P=98P=98 mm; S=πr2=π×15.62=243.36π764.5S=\pi r^2 = \pi \times 15.6^2 = 243.36\pi \approx 764.5 mm2.
  4. S=πr215.2=πr2r2=15.2πr=15.2π2.2S=\pi r^2 \rArr 15.2=\pi r^2 \rArr r^2=\dfrac{15.2}{\pi} \rArr r=\sqrt{\dfrac{15.2}{\pi}} \approx 2.2 m; d=2r=2×2.2=4.4d=2r=2 \times 2.2 = 4.4 m; P=2πr=2×π×2.2=4.4π13.8P=2\pi r = 2 \times \pi \times 2.2 = 4.4\pi \approx 13.8 m; S=15.2S=15.2 m2.