Question

Simplifique as expressões: a) x.(2x - 1) + x . ( 1 - 3x) b) ( a + 5) . ( a - 5 ) - ( a + 5)2 c) y. ( y+2) - 2y . ( 3 - y) d) (2 + x)2 - (x+2)2

Answer 1

a) x.(2x - 1) + x( 1 - 3x) =  2x2 - x + x - 3x2 ==> - x2
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b)(a+5)(a-5)-(a+5)2 = a2 - 25 -(a2+10a+25) =>a2-25-a2-10a-25 => -10a - 25 
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c) y. ( y+2) - 2y . ( 3 - y) = y2+2y-6y+2y2 ==>3y2 - 3y 
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d) (2 + x)2 - (x+2)2= 0