we are given
[tex] 12-24+48-96 [/tex]
we can see that
total number of terms is 4
so, n=4
first term is 12
[tex] a_1=12 [/tex]
[tex] a_2=-24 [/tex]
now, we can find common ratio
[tex] r=\frac{-24}{12} [/tex]
[tex] r=-2 [/tex]
now, we can find nth term
[tex] a_n=a_1 (r)^{n-1} [/tex]
[tex] a_n=12 (-2)^{n-1} [/tex]
so,
option-B.........Answer
