Question

Simplificati fractia pana devine ireductibila


5 la puterea 21 -5 la puterea 20 supra 5 la puterea 21

Answer 1

$\dfrac{5^{21}-5^{20}}{5^{21}}=\dfrac{5^{20}(5-1)}{5^{21}}=\boxed{\dfrac{4}{5}}$

Answer 2

5²¹ - 5²⁰      5²⁰(5 - 1)        4
----------  = -------------- = -------
   5²¹           5²⁰ x 5            5

5²¹=5²⁰ x 5 adica 5⁽²⁰⁺¹⁾
il dau factor comun pe 5²⁰