Géométrie

Surface d'un cerlce

Surface d'un cercle


<Surfacecercle />


## Comment calculer l'aire / la surface d'un cercle ?
<div className="flex flex-col md:flex-row items-center">
  <div>
    <svg className="h-32 w-32 lg:h-40 lg:w-40" viewBox="0 0 300 300" version="1.1">
      <g id="Rond" stroke="none" strokeWidth={1} fill="none" fillRule="evenodd">
        <rect id="Rectangle" stroke="#C3DDFD" strokeWidth={5} fill="#EBF5FF" x="51.5" y="51.5" width={197} height={197} rx="98.5" />
        <text id="R" fontFamily="ProximaNova-MediumIt, Proxima Nova" fontSize={20} fontStyle="italic" fontWeight={500} letterSpacing="0.2" fill="#9FA6B2">
          <tspan x={168} y={114}>R</tspan>
        </text>
        <circle id="Oval" fill="#C3DDFD" cx={150} cy={150} r={2} />
        <path id="Line-3" d="M216.529034,78.3814846 L216.325205,79.2466882 L214.220443,88.1808907 L214.105789,88.6675677 L213.132435,88.4382603 L213.247089,87.9515832 L214.913,80.875 L210.813363,85.3326618 L152.617966,148.588528 L152.279437,148.956494 L151.543506,148.279437 L151.882034,147.911472 L210.077432,84.6556053 L214.178,80.197 L207.265129,82.4481804 L206.789677,82.6029228 L206.480192,81.6520185 L206.955644,81.497276 L215.683786,78.6565823 L216.529034,78.3814846 Z" fill="#9FA6B2" fillRule="nonzero" />
      </g>
    </svg>
  </div>
  <div>
    <p>Pour calculer l'aire (la surface) d'un disque, il faut multiplier le carré du rayon (R) par π.</p>
  </div>
</div>

$
air = \pi \times  R^2
$

## Comment calculer le périmètre d'un cercle ?
Pour calculer le périmètre d'un cercle, il faut multiplier le rayon (R) par 2 et par π.

$
perimetre = 2 \pi \times  R
$