Question

Va rog să mă ajutați cu exercițiile încercuite

Answer 1

a) 1 /3 + (1 / 3)^-2 × 1 / 9 =

1 / 3 + 3^2 × 1 / 9 =

1 / 3 + 9 / 9 =

1 / 3 + 1 =

4 / 3
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( 1 / 3 )^-2 = 1 / (1 / 3)^2 = 1 / (1 / 9) = 9

b)

( 1 / 2)^-1 + ( 1 / 2)^-2 + ( 1 / 2) ^ - 3 =

2^1 + 2^2 + 2^3 =

2 + 4 + 8 =

14
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( 1 / 2 )^-1 = 1 / (1/2)^1 = 1 / (1/2) = 2

(1 / 2)^-2 = 1 / (1 / 2)^2 = 1 / (1 / 4) = 4

( 1 / 2)^-3 = 1 / ( 1 / 2)^3 = 1 / (1 / 8) = 8



c) 2^-1 = 1 / 2^1 = 1 / 2

2^-2 = 1 / 2^2 = 1 / 4


2 - ( 2^-1 + 2^-2) =

2 - ( 1 / 2 + 1 / 4) =

2 - ( 2 + 1 ) / 4 =

2 - 3 / 4 =

( 2 × 4 - 3 ) / 4 =

( 8 - 3 ) / 4 =

5 / 4
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