DÉTERMINER&UNE&VALEUR&DU&COSINUS&ET&DU&SINUS&
D’UN&NOMBRE&RÉEL&DONNÉ&
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Proposition&de&résolution&
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H:4-!4/37,!,C,01>,B!4/<-!.A/6-6--/4-!9,!37:5:6>>,7!,4!
7:96:4-?!
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+,-!96;;27,43,-!;/4.36/4-!376D/4/02376R<,-!-/43!:..,--6]>,-!8!1:7367!9,!>:!3/<.A,!
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'/<-!/]3,4/4-!>,!0,4<!./43,C3<,>!-<65:43!@!!
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+,!.A/6C!9,!>:!;/4.36/4!92-672,!-E,;;,.3<,!8!
+E:69,!9,-!3/<.A,-!967,.36/44,>>,-?!
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Q64-6B!/4!1,<3!.:>.<>,7B!1:7!,C,01>,B!sin $
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(!-E/]36,43!:5,.!!
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\/<7!/]3,467!>:!5:>,<7!:117/.A2,B!.>6R<,7!-<7!!
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Remarque&
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