## koli123able Group Title Find 'p' if 3x^2+2x+3p=0 has real & different roots. . . ANSWER = p<1/9 one year ago one year ago

1. koli123able Group Title

I have no idea on solving this question....

2. Xavier Group Title

A quadratic has real and different roots if the descriminant is greater than zero: $\Delta > 0$

3. koli123able Group Title

delta?? u mean discriminant?

4. ParthKohli Group Title

Yes.

5. Xavier Group Title

Yup

6. koli123able Group Title

so how D>0 ??

7. Xavier Group Title

What do you mean? Set the discriminant to be greater than zero b^2-4ac > 0

8. koli123able Group Title

I mean how is discriminant greater than zero can u explain?

9. harsimran_hs4 Group Title

if d > 0 then there are real and different roots d = 0 real and equal roots d < 0 imaginary roots

10. agent0smith Group Title

Real and different...? I'm guessing you mean real and distinct. But yes you can use the discriminant. When the discriminant is less than zero, it will have complex/imaginary roots, as the quadratic formula takes the square root of the discriminant ( http://www.purplemath.com/modules/quadform.htm ) $3x^2+2x+3p=0$$ax^2+bx+c = 0$ so here, a=3, b = 2 and c = 3p discriminant is $b^2-4ac > 0$

11. koli123able Group Title

If D>0 then sqrt(b^2-4ac) is a real number and roots are real and unequal

12. koli123able Group Title

am I right?

13. harsimran_hs4 Group Title

$x = \frac{ -b \pm \sqrt{b^2 - 4ac} }{ 2a }$ try putting different values of d and check out

14. harsimran_hs4 Group Title

yes you are!!

15. koli123able Group Title

as D>0 and D=b^2-4ac so, (2)^2-4*3*3p>0 4-36p>0 4>36p 1/9>0

16. koli123able Group Title

is this ok?

17. Xavier Group Title

You lost a p at the end

18. koli123able Group Title

oh sorry I typed it in hurry

19. koli123able Group Title

p<1/9