Question

Quantos e 5ⁿ+5¹+5-²=

Answer 1

5^n + 5 + 1/5²
5^n + 5 + 1/25
25.5^n + 125 + 1/25
25.5^n + 126/25 

Answer 2

Olá.

$\mathsf{5^n+5^1+5^{-2}=5^n+5^1+\dfrac{1}{5^{2}}=\dfrac{5^2\cdot5^n+5^2\cdot5^1+1}{5^2}=}\\\\\\\mathsf{\dfrac{5^2\cdot5+5^3+1}{5^2}=\dfrac{5^2\cdot5^n}{5^2}+\dfrac{5^3+1}{5^2}=5^n+\dfrac{125+1}{25}=\boxed{\mathsf{5^n+\dfrac{126}{25}}}}$

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Bons estudos.