Step 1

\(\displaystyle{2}^{{-{1.5}}}={\frac{{{1}}}{{{2}^{{{1.5}}}}}}\)

\(\displaystyle={\frac{{{1}}}{{{2}^{{{\frac{{{3}}}{{{2}}}}}}}}}\)

\(\displaystyle={\frac{{{1}}}{{\sqrt{{{2}^{{{3}}}}}}}}\)

\(\displaystyle={\frac{{{1}}}{{{2}\sqrt{{{2}}}}}}\)

\(\displaystyle{2}^{{-{1.5}}}={\frac{{{1}}}{{{2}^{{{1.5}}}}}}\)

\(\displaystyle={\frac{{{1}}}{{{2}^{{{\frac{{{3}}}{{{2}}}}}}}}}\)

\(\displaystyle={\frac{{{1}}}{{\sqrt{{{2}^{{{3}}}}}}}}\)

\(\displaystyle={\frac{{{1}}}{{{2}\sqrt{{{2}}}}}}\)