Answer
$a_1 = 1$
$a_2 = 0$
$a_3 = -3$
$a_4 = -8$
$a_5 = -15$
Work Step by Step
Substitute numbers $1$ through $5$ to find the first five terms of this series:
For $n = 1$:
$a_1 = -(1)^2 + 2(1)$
Evaluate exponents first, according to order of operations:
$a_1 = -1 + 2(1)$
Multiply next:
$a_1 = -1 + 2$
Add to simplify:
$a_1 = 1$
For $n = 2$:
$a_2 = -(2)^2 + 2(2)$
Evaluate exponents first, according to order of operations:
$a_2 = -4 + 2(2)$
Multiply next:
$a_2 = -4 + 4$
Add to simplify:
$a_2 = 0$
For $n = 3$:
$a_3 = -(3)^2 + 2(3)$
Evaluate exponents first, according to order of operations:
$a_3 = -9 + 2(3)$
Multiply next:
$a_3 = -9 + 6$
Add to simplify:
$a_3 = -3$
For $n = 4$:
$a_4 = -(4)^2 + 2(4)$
Evaluate exponents first, according to order of operations:
$a_4 = -16 + 2(4)$
Multiply next:
$a_4 = -16 + 8$
Add to simplify:
$a_4 = -8$
For $n = 5$:
$a_5 = -(5)^2 + 2(5)$
Evaluate exponents first, according to order of operations:
$a_5 = -25 + 2(5)$
Multiply next:
$a_5 = -25 + 10$
Add to simplify:
$a_5 = -15$
