Show that there is no value of n for which (2” × 5”) ends in 5.

(2” × 5”) = 10n {using rules of exponent}

And 10n either ends up with 1 for n = 0 and for n>0 and integer, ends up with zero.


Also for negative value of n it ends with fractions not ending with 5.


this will never end with 5.


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