( 5 * 4^27 - 21 * 4^26 ) / 2^50 =
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1) 5 * 2 ^54 - 21 * 2 ^ 52 = 2 ^ 52 * ( 5 * 2^2 - 21 ) = 2^52 * ( - 1 )
2) ( 2 ^ 52 * ( - 1 ) ) / ( 2 ^ 50) = 2 ^ 2 * ( - 1 ) = 4 * ( - 1 ) = ( - 4 )
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ответ ( - 4 )