Question

$\frac{2}{5} {a}^{ - 3} {b}^{} \times \frac{15}{16} {a}^{ - 2} {b}^{ - 3 }$
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Answer 1

$\frac{2}{5}a^{-3}b\frac{15}{16}a^{-2}b^{-3}$

$=\frac{2}{5}a^{-3-2}b\frac{15}{16}b^{-3}$

$=\frac{2}{5}a^{-5}b\frac{15}{16}b^{-3}$

$=\frac{2}{5}\times \frac{1}{a^5}b\frac{15}{16}b^{-3}$

$=\frac{2}{5}\times \frac{1}{a^5}b^{1-3}\frac{15}{16}$

$=\frac{2}{5}\times \frac{1}{a^5}\times \frac{1}{b^2}\times \frac{15}{16}$

$=\frac{3}{8a^5b^2}$

ответь:

$=\frac{3}{8a^5b^2}$