Find "n" such that (-3)ⁿ⁺¹ X (-3)⁵  = (-3)⁷

Dear Student,

Please find the below required solution.

$$\begin{gathered} {\left(-3\right)}^{n+1}\times (-3{)}^5 = (-3{)}^7 \\ (-3{)}^{n+1+5} = (-3{)}^7 [ \sin ce a^m{a}^n = a^{m+n} ] \\ (-3{)}^{n+6} = (-3{)}^7 \\ \Rightarrow n+6 = 7 [ \sin ce a^m = a^{n } \Rightarrow m = n ] \\ \Rightarrow n = 7-6 \\ \Rightarrow n = 1 \end{gathered}$$

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