Find the Third Term 3n^2-1

$3 n^{2} - 1$

Substitute in the value of $n$ to find the $n$ th term.

$a_{3} = 3 {(3)}^{2} - 1$

Simplify each term.

Multiply $3$ by ${(3)}^{2}$ by adding the exponents.

Multiply $3$ by ${(3)}^{2}$ .

Raise $3$ to the power of $1$ .

$a_{3} = 3 {(3)}^{2} - 1$

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$a_{3} = 3^{1 + 2} - 1$

Add $1$ and $2$ .

$a_{3} = 3^{3} - 1$

Raise $3$ to the power of $3$ .

$a_{3} = 27 - 1$

Subtract $1$ from $27$ .

$a_{3} = 26$