Multiple Progressions?

Algebra Level 2

$\large 1\; , \; \text{\_\_} \; , \; 4$

The above shows the first 3 terms of a geometric progression with the second term not shown.

Can we uniquely determine the value of this second term?

Yes No

1 solution

Zee Ell
Sep 12, 2016

$a = 1$

$ar^2 = 4$

$r^2 = \frac {4}{1} = 4$

$r = ± 2$

Therefore, the first 3 terms of this geometric progression can either be:

1, - 2 , 4 or 1, 2, 4

Hence, our answer is:

$\boxed {No}$

Ahhhh I always forget to do negative values I'm too used to calculating positive values.

Rico Lee - 4 years, 9 months ago