利用公式法,解下列各題,答案以根式表示。 (急需)

(1) x^2 3x - 3 = 0

x = {-3 √[3^2 -4(1)(-3)]}/2

= (-3 √21)/2

= 0.79 or -3.79

(2) 8x^2 - x - 4 = 0

x = {1 √[1^2 -4(8)(-4)]}/[2(8)]

= (1 √129)/16

= 0.77 or -0.65

(3) x^2 5x - 2 = 0

x = {-5 √[5^2 - 4(1)(-2)]}/2

= (-5 √33)/2

= 0.37 or -5.37

(4) -6x^2 4x 1 = 0

6x^2 - 4x - 1 = 0

x = {4 √[4^2 - 4(6)(-1)}/[2(6)]

= (4 √40)/12

= 0.86 or -0.19

(5) 5x^2 - 3x 1 = 0

x = {3 √[3^2 - 4(5)(1)]}/[2(5)]

= ( 3 √-11)/10

= ?

(6) 5x^2 - 30 = 0

5(x^2 - 6) = 0

5 (x - √6) (x √6) = 0

x = √6

(1) x^2 + 3x - 3 = 0
x = {-3 √[3^2 -4(1)(-3)]}/2
= (-3 √21)/2
= 0.79 or -3.79
(2) 8x^2 - x - 4 = 0
x = {1 √[1^2 -4(8)(-4)]}/[2(8)]
= (1 √129)/16
= 0.77 or -0.65
(3) x^2 + 5x - 2 = 0
x = {-5 √[5^2 - 4(1)(-2)]}/2
= (-5 √33)/2
= 0.37 or -5.37
(4) -6x^2 + 4x + 1 = 0
6x^2 - 4x - 1 = 0
x = {4 √[4^2 - 4(6)(-1)}/[2(6)]
= (4 √40)/12
= 0.86 or -0.19
(5) 5x^2 - 3x + 1 = 0
x = {3 √[3^2 - 4(5)(1)]}/[2(5)]
= ( 3 √-11)/10
= no solution
(6) 5x^2 - 30 = 0
5(x^2 - 6) = 0
5 (x - √6) (x + √6) = 0
x = √6