PLEASE HELP!! What are the explicit equation and domain for a geometric sequence with the first term of 3 a second term of -9?

The correct answer is c.

the third option

Step-by-step explanation:

a1 = 3

a2 = -9

as a geometric sequence every sequence item is created by multiplying a constant factor with the previous item.

what do I need to multiply 3 with to get -9 ? right, -3.

so, the first 2 options are out, because they multiply with -12.

and we can accept only n>=1, because there is no a0. it starts with a1.

ah only the third option is right.

problem:

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

f(5/2) = 10/3

i hope this !

i think the correct option is the second option.