Ẓṛ asagm n Talɣa:Aggur:Tusnakt/Anɣmis g Lqist n ɣassa

[[File:Triangle with notations 2.svg|thumb|Fig. 1]]
Ɣ [[Asktiɣmr|taskriɣmrt]], '''Asaḍuf n id kusinus''' (ittawsan ula s yism n '''tanfalit n kusinus''' nɣ '''askkud n Al Kaci''') tga yan usaḍuf nna ismunn tiɣziwin n tasgiwin n kra n umkṛaḍ d kusinus n yan zɣ tiɣmriwin. S uswuri n tirra zund tin Fig. 1, asaḍuf n iwankn n id kusinus

<math>c^2 = a^2 + b^2 - 2ab\cos\gamma,</math>

maɣ <math>\gamma</math> tga tiɣmrt lli illan gr tiɣziwin <math>a</math> d <math>b</math> d tasga tamuzzlt n <math>c</math>. I tawlaft ann nit rad darnɣ ilin ula:

<math>a^2=b^2+c^2-2bc\cos\alpha,</math>

<math>b^2=a^2+c^2-2ac\cos\beta.</math>

Asaḍuf n id kusinus ar tskar asmata i [[Askkud n Pythagor|askkud n Pythagor]], nna ur illan dar imkṛaḍn unziɣn: iɣ tga <math>\gamma</math> tiɣmrt taɣadant (nna dar illa 90 daraja, nɣ <math display="inline">{\pi \over 2}</math> s raḍyan), hann <math display="inline">cos(\gamma)=0</math>, s ɣmk ad as iskar usaḍuf n id kusinus asmata i [[Askkud n Pythagor|askkud n Pythagor]]:

<math>c^2 = a^2 + b^2.</math>

Ar nswurri s usaḍuf n id kusinus n id kusinus iɣ nra ad nḥasb tiɣmrt tiss kraḍt n kra n umkṛaḍ iɣ yad tawssan darnɣ snat tasgiwin d tiɣmrt nnsn iqqnn, d ula ɣ lḥsab n tiɣmriwin n kra n umkṛaḍ iɣ yad ttawssan darnɣ tasgiwin nns s kraḍ-itsnt. ([[Asaḍuf n id kusinus|'''Ɣr uggar'''...]])