Eu tenho as respostas mas preciso montar a conta. Mas não to conseguindo fazer a baskara :( me ajudem
b) x² - 5x + 6 = 0
c) x² - 8x + 12 = 0
d) x² + 2x – 8 = 0
e) x² - 5x + 8 = 0
f) 6x² + x – 1 = 0
g) 2x² - 8x + 8 = 0
h) x² = 7x – 10 ( passe 7x – 10 para o primeiro membro da equação com a operação
x² - 7x + 10 = 0 inversa, e iguale a zero a equação).
i) 2x² - 3 = x
j) 2 + 3x + x² = 0
k) x² + 2x + 2 = 5
b) S = { 2,3}
c) S = { 2,6}
d) S = { 2, -4}
e) S = { }
f) S = {1/3 , -1/2}
g) S = { 2 }
h) S = { 2, 5 }
i) S = { 3/2, -1}
j) S = { -1, -2}
k) S = { -3, 1 }
Soluções para a tarefa
B) x² - 5x + 6 = 0
a = 1
b = -5
c = 6
Delta:
Δ = b² - 4ac
Δ = (-5)² - 4 * 1 * 6
Δ = 25 - 24
Δ = 1
Bhaskara:
x = - b ± √Δ / 2a
x = - (-5) ± √1 / 2 * 1
x = 5 ± 1 / 2
x' = 5 + 1 / 2 = 6 / 2 = 3
x'' = 5 - 1 / 2 = 4 / 2 = 2
S = {2, 3}
C) x² - 8x + 12 = 0
a = 1
b = -8
c = 12
Delta:
Δ = b² - 4ac
Δ = (-8)² - 4 * 1* 12
Δ = 64-48
Δ = 16
Bhaskara:
x = - b ± √Δ / 2a
x = - (-8) ± √16/ 2 * 1
x = 8± 4/ 2
x' = 8 + 4/ 2 = 12 / 2 = 6
x'' = 8 - 4 / 2 = 4 / 2 = 2
S = {2,6}
D) x² +2x -8 = 0
a = 1
b = 2
c = -8
Delta:
Δ = b² - 4ac
Δ = (2)² - 4 * 1 * (-8)
Δ = 4+32
Δ = 36
Bhaskara:
x = - b ± √Δ / 2a
x = -2 ± √36 / 2 * 1
x = -2 ± 36/ 2
x' = -2 + 6/ 2 = 4/ 2 = 2
x'' = -2 - 6/ 2 = -8 / 2 = -4
S = {2, -4}
E) x² - 5x + 8 = 0
a = 1
b = -5
c = 8
Delta:
Δ = b² - 4ac
Δ = (-5)² - 4 * 1 * 8
Δ = 25 -32
Δ = -7
S ={ }
F)6x² + x – 1 = 0
a = 6
b = 1
c = -1
Delta:
Δ = b² - 4ac
Δ = (1)² - 4 * 6* (-1)
Δ = 1+24
Δ = 25
Bhaskara:
x = - b ± √Δ / 2a
x = -1 ± √25 / 2 *6
x = -1 ± 25/ 12
x' = -1 + 5/ 12= 4 / 12= 2/6= 1/3
x'' = -1 - 5/ 12 = -6/12= 2/4=-1/2
S= {1/3,-1/2}
g) 2x² - 8x + 8 = 0
a = 2
b = -8
c = 8
Delta:
Δ = b² - 4ac
Δ = (-8)² - 4 * 2* 8
Δ = 64-64
Δ = 0
Bhaskara:
x = - b ± √Δ / 2a
x = - (-8) ± √0 / 2 *2
x = 8 ± 0/ 4
x' = 8 + 0/ 4= 8/4= 2
x'' = 8- 0/ 4 = 8/4= 2
S={2}
H) x² = 7x – 10
x² -7x+10= 0
a = 1
b = -7
c = 10
Delta:
Δ = b² - 4ac
Δ = (-7)² - 4 * 1 * 10
Δ = 49-40
Δ = 9
Bhaskara:
x = - b ± √Δ / 2a
x = - (-7) ± √9/ 2 * 1
x = 7± 9 / 2
x' = 7+ 3 / 2 = 10/2=5
x'' = 7 - 3 / 2 = 4/2=2
S={2,5}
I) 2x² - 3 = x
2x²-x-3=0
a = 2
b = -1
c = -3
Delta:
Δ = b² - 4ac
Δ = (-1)² - 4 * 2 * (-3)
Δ = 1+24
Δ = 25
Bhaskara:
x = - b ± √Δ / 2a
x = - (-1) ± √25/ 2 * 2
x = 1± 5 / 4
x' = 1+ 5/ 4 = 6/4= 3/2
x'' = 1 - 5 / 4 = -4/4= -1
S={3/2,-1}
j)
x²+3x+2=0
a = 1
b = 3
c = 2
Delta:
Δ = b² - 4ac
Δ = 3² - 4 * 1 *2
Δ = 9-8
Δ= 1
Bhaskara:
x = - b ± √Δ / 2a
x = - 3 ± √1/ 2 * 1
x =- 3± 1/ 2
x' = -3+1/ 2 =-2/2 = -1
x'' = -3- 1/ 2= -4/2 =-2
S= {-1,-2}
K) x² + 2x + 2 = 5
x² + 2x -3 = 0
a = 1
b = 2
c = -3
Delta:
Δ = b² - 4ac
Δ = 2²- 4 * 1*(-3)
Δ = 4+12
Δ= 16
Bhaskara:
x = - b ± √Δ / 2a
x = - 2± √16/ 2 * 1
x =- 2± 4/ 2
x' = -2+4/ 2 = 2/2= 1
x'' = -2- 4/ 2= -6/2= -3
S= {-3,1}