dijawab kawan beserta caranya ya untuk yang terbaik dapet poin 15

1. x1 = 1/5 , x2 = -5
x1 + x2 = 1/5 - 5
= -24/5
x1 . x2 = 1/5 . (-5)
= -1
—> x² - (x1 + x2)x + x1.x2 = 0
x² + 24/5 -1 = 0
5x² + 24 - 5 = 0

2. cos 225° = cos (2.90°+45°)
= - cos 45°
= - ½ √2

3. Lim x->6 (1 - x) / (2 - √x+3)
=( 1 - 6 ) / (2 - √6+3)
= -5 / (2 - √9)
= -5 / (2-3)
= -5 / -1
= 5

4. jumlah bil.prima ganjil = 2 (3,5)
P(a) = 2 / 6
= 1/3

5. PQ = 10cm , QR = 20cm, <Q = 30°
L.PQR = ½ PQ . QR . sin Q
= ½ . 10 . 20 . ½
= 50cm²