tentukan suku ke 10 jika U5 = -6 dan U6 = -9

U5 = a + (n-1) b = a+4b = -6
U6 = a + (n-1) b = a+5b = -9 -
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-b = 3
b = -3

U5 = a + (n-1) b = -6
a + 4(-3) = -6
a = -6 + 12
a = 6

U10 = a + (n-1) b
= 6 + 9 (-3)
= 6 + (-27)
= -21

Semoga bermanfaat