Question

Find the 10th term in the sequence.

1/2, -1, 2, -4

1. 512
2. 125
3. -256

Answer 1

Explanation:

everything can be found in the picture

Answer 2

tenth term is -256

Explanation:

It is geometric progression:

`a_(n) = a( {r}^(n-1) )`

r » common ratio, r = 2 ÷ (-1) = -2

a » first term, a = ½

n » number of terms, n is 10

`a_(10) = (1)/(2) \{{( - 2)}^(10-1) \} \\ \\ a_(10) = (1)/(2) (-512) \\ \\ a_(10) = (-256)/(1)`