Find the first, fourth, and eighth terms of the sequence. A(n) = −5 ∙ 2^x-1 –5; –40; –640 –20; –160; –2,560 –10; –80; –1,280 1; –1,000; –10,000,000
The given sequence is described by the formula A(n) = −5 ∙ 2^(n-1).
To find the first term, substitute n = 1 into the formula:
A(1) = −5 ∙ 2^(1-1) = −5 ∙ 2^0 = -5.
To find the fourth term, substitute n = 4 into the formula:
A(4) = −5 ∙ 2^(4-1) = −5 ∙ 2^3 = -5 ∙ 8 = -40.
To find the eighth term, substitute n = 8 into the formula:
A(8) = −5 ∙ 2^(8-1) = −5 ∙ 2^7 = -5 ∙ 128 = -640.
Therefore, the first, fourth, and eighth terms of the sequence are -5, -40, and -640, respectively.