Maths Quadratic equation

2010-12-29 8:58 pm
If β is a root of 3x^2+2x-3 ,then,6^β2+4β-7=0

p is non zero root of the x^2-px+q=0 Which one is true?
q>0
q=0
Zero is the other root


更新1:

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更新2:

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回答 (3)

2010-12-29 10:11 pm
✔ 最佳答案
QUESTION 1 If β is a root of 3x^2+2x-3=0 ,then,6β^2+4β-7=?

Since 3β^2+2β-3=0, 6β^2+4β-7=2(3β^2+2β-3)-1=2*0-1=-1

QUESTION 2 p is non zero root of the x^2-px+q=0 Which one is true?
q>0
q=0
0 is the other root

We have p^2-p*p+q=0 => q=0 => II is true

Now x^2-px+q=0 => x^2-px=0 => 0 is the other root => III is true


2010-12-29 9:06 pm
as zero is the other root:
subs x=0 into the eqn,

q=0



2010-12-29 9:03 pm
6^β2 = (6^β)*2?
or = (6^2β)?


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