Question

Question 2(v)
Simplify and express the result in power notation with positive exponent:

$2^{-3}\times (-7{)}^{-3}$

Answer 1

$2^{-3}\times (-7{)}^{-3}=\frac{1}{2^3}\times \frac{1}{(-7{)}^3}[\because a^{-m}=\frac{1}{a^m}]=\frac{1}{{\{2\times (-7\left)\right\}}^3}=\frac{1}{(-14{)}^3}[\because (ab{)}^m=a^m{b}^m]$