Evaluate -2^-1-2^0-2^-2

$- 2^{- 1} - 2^{0} - 2^{- 2}$

Simplify each term.

Rewrite the expression using the negative exponent rule $b^{- n} = \frac{1}{b^{n}}$ .

$- \frac{1}{2} - 2^{0} - 2^{- 2}$

Anything raised to $0$ is $1$ .

$- \frac{1}{2} - 1 \cdot 1 - 2^{- 2}$

Multiply $- 1$ by $1$ .

$- \frac{1}{2} - 1 - 2^{- 2}$

Rewrite the expression using the negative exponent rule $b^{- n} = \frac{1}{b^{n}}$ .

$- \frac{1}{2} - 1 - \frac{1}{2^{2}}$

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

$- \frac{1}{2} - 1 - \frac{1}{4}$

Find the common denominator.

Multiply $\frac{1}{2}$ by $\frac{2}{2}$ .

$- (\frac{1}{2} \cdot \frac{2}{2}) - 1 - \frac{1}{4}$

Multiply $\frac{1}{2}$ by $\frac{2}{2}$ .

$- \frac{2}{2 \cdot 2} - 1 - \frac{1}{4}$

Write $- 1$ as a fraction with denominator $1$ .

$- \frac{2}{2 \cdot 2} + \frac{- 1}{1} - \frac{1}{4}$

Multiply $\frac{- 1}{1}$ by $\frac{4}{4}$ .

$- \frac{2}{2 \cdot 2} + \frac{- 1}{1} \cdot \frac{4}{4} - \frac{1}{4}$

Multiply $\frac{- 1}{1}$ by $\frac{4}{4}$ .

$- \frac{2}{2 \cdot 2} + \frac{- 1 \cdot 4}{4} - \frac{1}{4}$

Multiply $2$ by $2$ .

$- \frac{2}{4} + \frac{- 1 \cdot 4}{4} - \frac{1}{4}$

Combine the numerators over the common denominator.

$\frac{- 2 - 1 \cdot 4 - 1}{4}$

Simplify the expression.

Multiply $- 1$ by $4$ .

$\frac{- 2 - 4 - 1}{4}$

Subtract $4$ from $- 2$ .

$\frac{- 6 - 1}{4}$

Subtract $1$ from $- 6$ .

$\frac{- 7}{4}$

Move the negative in front of the fraction.

$- \frac{7}{4}$

The result can be shown in multiple forms.

Exact Form:

$- \frac{7}{4}$

Decimal Form:

$- 1.75$

Mixed Number Form:

$- 1 \frac{3}{4}$