Find the discriminant: 2x^2-6x+2=0
a)2sqrt5
b)20
c)-20
d)-2sqrt5
e) none
Find the discriminant: 2x^2-6x+2=0?
2009-05-10 9:47 am
回答 (7)
2009-05-10 9:54 am
✔ 最佳答案
using the formula b^2-4acgiven a=2, b=-6, c=2
=(-6)^2-4(2)(2)
=36-16
=20
answer is b)20
2009-05-11 11:25 pm
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http://mathvariety.blogspot.com/2009/04/discriminant-in-quadratic-equation.html
http://mathvariety.blogspot.com/2009/05/discriminant-in-quadratic-equation.html
http://mathvariety.blogspot.com/2009/05/discriminant-in-quadratic-equation_11.html
The discriminant is b^2-4ac. Here, a=2, b= -6, c=2, so we have:
(-6)^2-4*2*2 which is 36-16 or 20. The answer is b.
The discriminant does not involve a radical sign. Someone who thought the discriminant involves the radical sign might have chosen a) or d) as the answer. This is wrong.
http://mathvariety.blogspot.com/2009/04/discriminant-in-quadratic-equation.html
http://mathvariety.blogspot.com/2009/05/discriminant-in-quadratic-equation.html
http://mathvariety.blogspot.com/2009/05/discriminant-in-quadratic-equation_11.html
The discriminant is b^2-4ac. Here, a=2, b= -6, c=2, so we have:
(-6)^2-4*2*2 which is 36-16 or 20. The answer is b.
The discriminant does not involve a radical sign. Someone who thought the discriminant involves the radical sign might have chosen a) or d) as the answer. This is wrong.
2009-05-10 10:36 am
b^2 -4ac
answer is b
there is two solution in this question
answer is b
there is two solution in this question
2009-05-10 10:03 am
the discriminant is defined as b^2 - 4*a*c
lets identify a, b and c
a is 2
b is -6
c is 2
from here we can simply do
-6^2 - 4 * 2 * 2 = 36-4*2*2 = 36-16 =20
hope this helps
lets identify a, b and c
a is 2
b is -6
c is 2
from here we can simply do
-6^2 - 4 * 2 * 2 = 36-4*2*2 = 36-16 =20
hope this helps
參考: wat we have been doing in school lately
2009-05-10 9:55 am
2x^2 - 6x + 2 = 0
x = [-b 屉(b^2 - 4ac)]/2a
a = 2
b = -6
c = 2
x = [-6 屉(36 - 16)]/2
x = [3 屉20]/2
(answer b)
x = [-b 屉(b^2 - 4ac)]/2a
a = 2
b = -6
c = 2
x = [-6 屉(36 - 16)]/2
x = [3 屉20]/2
(answer b)
2009-05-10 9:53 am
discriminant (D)=b^2-4ac
therefore the answer is =36-16=20
therefore the answer is =36-16=20
2009-05-10 9:52 am
My calculator (TI-Interactive) says x=((Sqrt5)+3)/2 or x=-(((Sqrt5)-3)/2)
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