Question

calcular as expreasões

Answer 1

a) a = - 2

= a³ - 5a
= (- 2)³ - 5.(- 2)
= - 8 + 10
= 2
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b) x = - 3 e y = 5

= x² - 2y
= (- 3)² - 2.5
= 9 - 10
= - 1
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c) a = - 2; b = - 7

= 3a² - b²
= 3.(-2)² - (-7)²
= 3.4 - (49)
= 12 - 49
= - 37
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d) a = - 3; b = 4

= 5a² + 3ab
= 5.(-3)² + 3.(-3).(4)
= 5.9 + 3.(-12)
= 45 - 36
= 9
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e) a = 2/3

a² + 4a
(2)² + 4. 2  =  4 + 8
(3)         3      9    3

mmc (3,9) = 9

4 + 24 = 33
   9         9