Réponses

  • Utilisateur Brainly
2013-12-15T15:50:51+01:00
An(BJS)= tan(32°) = BS/BJ

tan(BIS) = tan(20°) = BS/(BJ+20)

BS = BJ*tan(32°) = tan(20°)*(BJ+20)

on trouve facilement BJ

puis BS








BJ*tan(32°) = tan(20°)*(BJ+20)

BJ*tan(32°) = BJ*tan(20°)+20*tan(20°)

BJ*(tan(32°)-tan(20°)) = 20*tan(20°)

BJ = 20*tan(20°) / (tan(32°)-tan(20°))

BJ 7,2794/0,2609 27,90 m

BS = BJ*tan(32°)

BS 27,90 * 0,62487 17,434 m


Citation :
tan12=20/JS...

JS² = BS² + BJ²

JS 32,90 m

tan(12°) 0,212556561

20/JS 20/32,90 0,6079

tan(12°) 20/JS