(a^m)^n =a^(m*n)
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16 =2⁴ =(2²) =4².
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81 =3⁴ =(3²)² =9².
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256 =2⁸ =(2⁴)² =16²
256 =2⁸ =(2²)⁴ =4⁴.
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729 =9*81 =3⁶= (3²)³ =(3³)² * * * 6=2*3 * * *
3⁶=9³ =27²
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1000000 =10⁶
(10²)³ =100³ , (10³)² =1000² .