Jika suatu barisan aritmatika mempunyai U1= 48 dan U6= -32maka U3 x U5...

Diketahui :
U1 = a = 48
U6 = -32

Ditanya :
U3 × U5 = ?

Jawab :
Un = a + (n-1) b
U6 = 48 + (6-1) b
-32= 48 + 5b
-32-48 = 5b
-80= 5b
-16 = b

U3 = a + (n-1) b
= 48 + (3-1) (-16)
= 48 + 2 (-16)
= 48 - 32
= 16

U5 = a + (n-1) b
= 48 + (5-1) (-16)
= 48 + 4 (-16)
= 48 - 64
= -16

U3 × U5 = 16 × (-16)
= -256




Maaf kalau salah

Semoga membantu:)