1) ( X² + 25 ) / ( X² - 25 ) = ( X² + 25 ) / ( X - 5 )*( X + 5 )
2) - 5 / ( 5 - X ) = + 5 / ( X - 5 )
3) ( X² + 5X ) / ( X² - 10X + 25 ) = ( X * ( X + 5 ) ) / ( X - 5)*( X - 5 )
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(( 5 / ( X + 5 )) + (( X² + 25 ) / ( X - 5)*( X + 5 )) + (( 5 / ( X - 5 )) =
= ( 5 * ( X - 5 ) + X² + 25 + 5 *( X + 5 ) / ( X - 5 )*( X + 5 ) =
= ( 5X - 25 + X² + 25 + 5X + 25 ) / ( X - 5 )*( X + 5 ) =
( X^2 + 10X + 25 ) / ( X - 5)*( X + 5 ) = ( X + 5 )*( X + 5 ) / ( X - 5 )*( X + 5 ) =
= ( X + 5 ) / ( X - 5 )
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( X + 5 ) / ( X - 5 ) : ( X - 5 ) / ( X + 5 ) = ( X + 5 )^2 / ( X - 5 )^2
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X = 1
6^2 / ( - 4 )^2 = 36 / 16 = 2,25