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D = (2x+3)2 - 2(2x-1)(2x+3) + (2x-1)2 + 31
D = [(2x+3) - (2x-1)]2 + 31
D = (2x + 3 - 2x + 1)2 + 31
D = 42 + 31
D = 16 + 31
D = 47
\(\left(2x+3\right)\left(2x-3\right)=4x^2-9\)
\(\left(a^2+5\right)\left(5-a^2\right)=25-a^4\)
( 2x + 3 ) ( 2x - 3 )
= [ ( 2x )2 + 6x ] - ( 6x + 9 )
= ( 2x )2 + ( 6x - 6x ) + 9
= ( 2x )2 + 9
\(\left(2x-3\right)\left(x-2\right)\)
\(=2x^2-4x-3x-6\)
\(=2x^2-7x-6\)
\(\left(x+3\right)^2\)
\(=x^2+2x.3+3^2\)
\(=x^2+6x+9\)
a) ( 3x - 2 )( 4x + 5 ) - 6x( 2x - 1 )
= 12x2 + 7x - 10 - 12x2 + 6x
= 13x - 10
b) ( 2x - 5 )2 - 4( x + 3 )( x - 3 )
= 4x2 - 20x + 25 - 4( x2 - 9 )
= 4x2 - 20x + 25 - 4x2 + 36
= 61 - 20x
c) 2x3 - 5x2 + 7x - 6
= 2x3 - 3x2 - 2x2 + 3x + 4x - 6
= x2( 2x - 3 ) - x( 2x - 3 ) + 2( 2x - 3 )
= ( 2x - 3 )( x2 - x + 2 )
=> ( 2x3 - 5x2 + 7x - 6 ) : ( 2x - 3 ) = x2 - x + 2
a, (3x - 2 ) (4x + 5) - 6x (2x -1) = ( 7x + 15x -8x - 10 ) - ( 12x2 -6x ) = 7x2 + 15x - 8x -10 -12x2 + 6x = -5x2 + x - 10
a) \(2x\left(3x^2-5x+3\right)\)
\(=6x^3-10x^2+6x\)
b) \(-2x\left(x^2+5x-3\right)\)
\(=-2x^3-10x^2+6x\)
c) \(\frac{-1}{2}x^2\left(2x^3-4x+3\right)\)
\(=-x^5+2x^3-\frac{3}{2}x^2\)
a) 2x(3x2-5x+3)= 6x3-10x2+6x
b) -2x(x2+5x-3)= -4x3-10x2+6x
c) -1/2x2(2x3-4x+3)= -x5+2x2-3/2x
\(4x^2-6x+6x-9-4x^2-4x-1=-4x-10\)