Precalculus Examples

$f (- 2) = x^{4} + 2 x^{2} - 1$

Step 1

Replace the variable $x$ with $- 2$ in the expression.

$f (- 2) = {(- 2)}^{4} + 2 {(- 2)}^{2} - 1$

Step 2

Simplify the result.

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Step 2.1

Simplify each term.

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Step 2.1.1

Raise $- 2$ to the power of $4$ .

$f (- 2) = 16 + 2 {(- 2)}^{2} - 1$

Step 2.1.2

Raise $- 2$ to the power of $2$ .

$f (- 2) = 16 + 2 \cdot 4 - 1$

Step 2.1.3

Multiply $2$ by $4$ .

$f (- 2) = 16 + 8 - 1$

Step 2.2

Simplify by adding and subtracting.

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Step 2.2.1

Add $16$ and $8$ .

$f (- 2) = 24 - 1$

Step 2.2.2

Subtract $1$ from $24$ .

$f (- 2) = 23$

Step 2.3

The final answer is $23$ .

$23$

Step 3