Question

URGENT, EX. 2, DAU CORONITA!

Answer 1

${(3x - 1)}^{2} - 2 {(x + 2)}^{2} + 3(1 - x)(1 + x)$

$= {(3x)}^{2} - 2 \times 3x \times1 + {1}^{2} - 2( {x}^{2} + 2 \times x \times 2 + {2}^{2} ) + 3( {1}^{2} - {x}^{2} )$

$= {3}^{2} \times {x}^{2} - 6x + 1 - 2( {x}^{2} + 4x + 4) + 3(1 - {x}^{2} )$

$= 9 {x}^{2} - 6x + 1 - 2 \times {x}^{2} - 2 \times 4x - 2 \times 4 + 3 \times 1 + 3 \times ( - {x}^{2} )$

$= 9 {x}^{2} - 6x + 1 - 2 {x}^{2} - 8x - 8 + 3 - 3 {x}^{2}$

$= 4 {x}^{2} - 14x - 4$