Can you help me with this it's synthetic substitution or direct substitution

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[Eqn 3]

f(x) = x³ + 3x² + 6x - 11 when x = 5

f(x) = x³ + 3x² + 6x - 11f(5) = (5)³ + 3*(5)²+6*(5)-11f(5) = 125 + 3*(25) + 30 - 11f(5) = 125 + 75 + 30 - 11f(5) = 200 + 30 - 11f(5) = 230 - 11f(5) = 219

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[Eqn 4]

f(x)=x³ - x² + 12x - 15 when x = 1

f( x ) = x³ - x² + 12x - 15f( 1 ) = ( 1 )³ - ( 1 )² + 12( 1 ) - 15f( 1 ) = 1 - 1 + 12 - 15 f( 1 ) = 0 + 12 - 15f( 1 ) = -3

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[Eqn 5]

f(x) = 2x³ + 6x² + 4x + 8 when x = 2

f( x ) = 2x³ + 6x² + 4x + 8f( 2 ) = 2( 2 )³ + 6( 2 )² + 4( 2 ) +8f( 2 ) = 2( 8 ) + 6( 4 ) + 8 + 8f( 2 ) = 16 + 24 + 16f( 2 ) = 40 + 16 f( 2 ) = 56