Question

Упростите выражение:
  a2     a
----- - -----
a2-1  a+1

Answer 1

( a² /  ( a² - 1 )) - ( a / ( a + 1 )) = ( a² / ( a - 1 )( a + 1 )) - ( a / ( a + 1 )) =
= ( a² - a( a - 1 )) / ( ( a - 1 )( a + 1 )) = ( a² - a² + a ) / ( a² - 1 ) = 
= a / ( a² - 1 )

Answer 2

$dfrac{a^2}{a^2-1}- dfrac{a}{a+1}= dfrac{a^2-a(a-1)}{(a-1)(a+1)}= dfrac{a^2-a^2+a}{a^2-1}= dfrac{a}{a^2-1}$