Find the first, fourth, and eighth terms of the sequence. A(n)=-2•5^x-1

To find the first term, we need to substitute n = 1 into the given formula:

A(1) = -2*5^(1-1)
A(1) = -2*5^0
A(1) = -2*1
A(1) = -2

Therefore, the first term of the sequence is -2.

To find the fourth term, we substitute n = 4 into the formula:

A(4) = -2*5^(4-1)
A(4) = -2*5^3
A(4) = -2*125
A(4) = -250

Therefore, the fourth term of the sequence is -250.

To find the eighth term, we substitute n = 8 into the formula:

A(8) = -2*5^(8-1)
A(8) = -2*5^7
A(8) = -2*78125
A(8) = -156250

Therefore, the eighth term of the sequence is -156250.