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B (x) = ( 2 x - 1 ) - 3 ( 2 x + 1 ) ( 2 x - 1 )
B (2) = ( 4 - 1 ) - 3 ( 4 + 1 ) ( 4 - 1 )
B (2) = 3 - 3 ( 5 * 3 )
B ( 2) = 3 - 3 *15
B ( 2) = 3 - 45 = - 42
B (x)= 2 x - 1 - 3 ( 4 x² - 1 )
B (x) = 2 x - 1 - 12 x² + 3
B (x) = - 12 x² + 2 x + 2
B (2) = - 12 ( 2 )² + 2 *2 + 2
B ( 2) = - 48 + 4 + 2
B ( 2) = - 42
B (x) = ( 2 x - 1 ) ( - 6 x - 3 + 1 )
B ( x) = ( 2 x - 1 ) ( - 6 x - 2 )
B ( 2) = ( 4 - 1 ) ( - 12 - 2)
B ( 2) = 3 x - 14 = - 42
