i need help .really need to understand how to do this step by step. plz help someone. Question 7

[dev644]

 

[ksdhart2]

You're told that this particular polynomial has two equal roots. In order for this to be the case, what must be true about the discriminant of the polynomial? Which value(s) of $a$ ensure this condition holds?

 

[dev644]

OK thanks, I have solved it. Great community, keep the good work☺

 

[Denis]

Could you post your solution: it may help another student.
Thank you.

 

[pka]

Find the value of $\displaystyle a$ that causes $\displaystyle (3a-2)x^2-6ax+4a+1=0$ has a double root.

To have a double root the discriminate must be zero:
$\displaystyle \Delta=(-6a)^2-4(3a-2)(4a+1)=0$ SEE HERE

If $\displaystyle a=2$ the root is $\displaystyle 1.5$ SEE HERE

If $\displaystyle a=\frac{-1}{3}$then the root is $\displaystyle \frac{1}{3}$ SEE HERE

 

[Denis]

well...in other words...b^2 = 4ac

 

[dev644]

Why are u angry jomo?