Question

Bantuin dong yg jago matematika (trigonometri)

1.
Diket :
AC = 8
AB = 6
/_ A = 150(derajat)
Dit = L segitiga ABC

2.
Segitiga KLM
Sisi = 10,12,14
L segitiga KLM = ?

Answer 1

1. L = 1/2 × AC × AB × sin A
L = 1/2 × 8 × 6 × sin 150°
L = 24 × sin (180°-30°)
L = 24 × sin 30°
L = 24 × 1/2
L = 12 cm2

2. K = 10+12+14
K = 36

s = 1/2 × K
s = 1/2 × 36
s = 18

L = √[s . (s-a) . (s-b) . (s-c)]
L = √[18 . (18-10) . (18-12) . (18-14)
L = √(18 . 8 . 6 . 4)
L = √(2 . 3^2 . 2^3 . 2 . 3 . 2^2)
L = √(2^6 . 2 . 3^2 . 3)
L = 2^3 . 3 . √6
L = 24√6 cm2