The equivalent expression of (a⁻⁷ . b⁻²)⁻⁹ is a⁶³b¹⁸
using the law of indices,
[tex](a^{x}) ^{y} = a^{x X y} =a^{xy}[/tex]
Therefore, we multiply the inner exponent by the outer exponent.
(a⁻⁷ . b⁻²)⁻⁹ = a⁻⁷ ˣ ⁻⁹ b⁻² ˣ ⁻ ⁹
a⁻⁷ ˣ ⁻⁹ b⁻² ˣ ⁻ ⁹ = a⁶³b¹⁸
Therefore,
(a⁻⁷ . b⁻²)⁻⁹ = a⁶³b¹⁸
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