Question

calcule as expressao
a) (a-8)2=
b) (3x+5)2=
c) (2x+2)3=
d) (3a -1)3=
e) (b+2)3 =

Answer 1

a)
= (a - 8)²
= a² - 2.8a + 8²
= a² - 16a + 64
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b)
= (3x + 5)²

= (3x)² + 2.5.3x + 5²

= 9x² + 30x + 25
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c)
= (2x + 2)³

= (2x + 2)².(2x + 2)

= (4x² + 2.2x.2 + 4).(2x + 2)

= (4x² + 8x + 4).(2x + 2)

= 8x³ + 8x² + 16x² + 16x + 8x + 8

        3
= 8x  + 24x² + 24x + 8
------------------------------------------
d)
= (3a - 1)³

= (3a - 1)².(3a - 1)

= (9a² - 2.3a.1 + 1).(3a - 1)

= (9a² - 6a + 1).(3a - 1)

= 27a³ - 9a² - 18a² + 6a + 3a - 1

          3
= 27a   - 27a² + 9a - 1
-------------------------------------------------
e)
= (b + 2)³
= (b + 2)².(b + 2)
= (b² + 2.2b + 4).(b + 2)
= (b² + 4b + 4).(b + 2)
=  b³ + 2b² + 4b² + 8b + 4b + 8

       3
= b    + 6b² + 12b + 8