Verified answer

(2^x + 1/2^x)³ = 8^x +3*2^x + 3*2^-x + 8^-x

125 = 8^x + 8^-x + 3*(2^x + 2^-x)

125 = 8^x + 8^-x + 3*5

8^x + 8^-x = 125 - 3*5 = 125 - 15 = 110

pronto

2^x+2^-x=5

elevamos ao quadrado

4^x +4^-x +2 * 2^x * 2^-x = 25

4^x +4^-x +2 = 25

4^x +4^-x = 23

(4^x +4^-x )( 2^x+2^-x) = 23 *5

8^x +2^x +2^-x + 8^-x = 115

8^x +5 + 8^-x = 115

8^x+8^-x = 115-5

8^x+8^-x = 110

=================

2^x+2^-x=5

2^x+1/2^x=5 ....mmc 2^x

2^x*2^x +1=5.2^x

2^x*2^x -5.2^x = -1

2^x(1 -5) = -1

-4 . 2^x = -1

2² . 2^x = 1

2^(2+x) =2º

2+x = 0

x= -2

8^x+8^-x

8^(-2)+8^-(-2)

1/8²+8²

(1+ 8².8²) /8²

4097/64

Agr eu lembrei pq parei de estuda '-'

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