Question

Find the explicit formula for the given sequence.

-4, 12, -36, 108,...

a
a_n=-4·(-3)^{n-1}

b
a_n=4·3^{n-1}

c
a_n=15·3^{n-1}

d
a_n=5·3^{n-1}

Answer 1

Option a.) an = -4(-3)^(n-1)