Question

Comparati:a)5 la 8 cu 2 la15+2×4la 7; b)5 la 14 cu 3 la 21.

Answer 1

a)       5⁸ cu 2¹⁵ + 2 x 4⁷

2¹⁵ + 2 x ( 2² ) ⁷ = 2 ¹⁴ x ( 2 + 2 ) = 2 ¹⁴ x 4 = 2¹⁴ x 2² = 2¹⁶= ( 2² ) ⁸ = 4⁸

5⁸ >  4⁸ ==>  5⁸ >  2¹⁵ + 2 x 4⁷

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b)    5¹⁴  cu  3²¹

5¹⁴ = ( 5² ) ⁷ = 25⁷

3²¹ = ( 3³ ) ⁷ = 27⁷

==>   25⁷  <  27⁷ ==>   5¹⁴  <  3²¹