Odpowiedź:
Szczegółowe wyjaśnienie:
7.
a)
sin30° = 1/2 => 14/CB = 1/2 => CB = 24
kąt ACB to 180° - 30° - 90° = 60°
sin60° = √3/2 => AB/24 = √3/2 => AB = 12√3
więc obwód wynosi 36 + 12√3
b)
sin30°=1/2 => AB/2 = 1/2 => AB = 1
kąt ABD to 180° - 30° - 90° = 60°
sin60° = √3/2 => AD/2 = √3/2 => AD = √3
sin45° = √2/2 => DC/2 = √2/2 => DC = √2
kąt BDC to 180° - 45° - 90° = 45°
sin45° = √2/2 => CB /2 = √2/2 => CB = √2
więc obwód wynosi 1 + √3 + 2√2
c)
kąt BAC to 180° - 90° - 60° = 30°
sin30°=1/2 => 7/AC = 1/2 => AC = 14
sin60° = √3/2 => AB/14 = √3/2 => AB = 7√3
sin45° = √2/2 => 14/AD = √2/2 => AD = 28√2
kąt CAD to 180° - 45° - 90° = 45°
sin45° = √2/2 => CD/28√2 = √2/2 => CD = 14
więc obwód wynosi 7√3 + 21 + 28√2
