Evaluate 256^(-5/4)

$256^{- \frac{5}{4}}$

Step 1

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

$\frac{1}{256^{\frac{5}{4}}}$

Step 2

Simplify the denominator.

Rewrite $256$ as $4^{4}$ .

$\frac{1}{{(4^{4})}^{\frac{5}{4}}}$

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

$\frac{1}{4^{4 (\frac{5}{4})}}$

Cancel the common factor of $4$ .

Cancel the common factor.

$\frac{1}{4^{4 (\frac{5}{4})}}$

Rewrite the expression.

$\frac{1}{4^{5}}$

Raise $4$ to the power of $5$ .

$\frac{1}{1024}$

Step 3

The result can be shown in multiple forms.

Exact Form:

$\frac{1}{1024}$

Decimal Form:

$0.00097656 \dots$