Question

1) Calcule o valor numérico de b² - 4ac, para: a) a = -2, b = 3 e c = 1 b) a = 1, b = -2 e c = 2 c) a = 1, b = -1 e c = 2 d) a = 3, b = 0 e c = -8 e) a = 1, b = 3 e c = 0 f) a = 1, b = -7 e c = -8 g) a = -3, b = -2 e c = -1 h) a = 1, b = 0 e c = 0 i) a = 5, b = 0 e c = 0 j) a = 3, b = -1 e c = -5

Answer 1

a) a = - 2, b = 3 e c = 1

= 3² - 4.(-2).(1)

= 9 + 8

= 17

b) a = 1, b = -2 e c = 2

= (-2)² - 4.(1).(2)

= 4 - 8

= - 4

c) a = 1, b = -1 e c = 2

= (-1)² - 4.(1).(2)

= 1 - 8

= - 7

d) a = 3, b = 0 e c = -8

= 0² - 4.(3).(-8)

= 0 + 96

= 96

e) a = 1, b = 3 e c = 0

= 3² - 4.(1).(0)

= 9 - 0

= 9

f) a = 1, b = -7 e c = -8

= (-7)² - 4.(1).(-8)

= 49 + 32

= 81

g) a = -3, b = -2 e c = -1

= (-2)² - 4.(-3).(-1)

= 4 - 12

= - 8

h) a = 1, b = 0 e c = 0

= 0² - 4.(1).(0)

= 0 - 0

= 0

i) a = 5, b = 0 e c = 0

= 0² - 4.(5).(0)

= 0 - 0

= 0

j) a = 3, b = -1 e c = -5

= (-1)² - 4.(3).(-5)

= 1 + 60

= 61