Home
Class 12
MATHS
If b^(2)ge4ac for the equation ax^(4)+bx...

If `b^(2)ge4ac` for the equation `ax^(4)+bx^(2)+c=0` then all the roots of the equation will be real if

A

`bgt0,alt0,cgt0`

B

`blt0,agt0,cgt0`

C

`bgt0,agt0,cgt0`

D

`bgt0,alt0,clt0`

Text Solution

Verified by Experts

The correct Answer is:
B, D

Put `x^(2)=y`
Then the given equation can be writte as
`f(y)=ay^(2)+by+c=0`……….i
The givenn equation will have real roots i.e. Eq. (i) has two non-negative roots.
Then `-b/age0` ltbr `af(0)ge0`
and `b^(2)-4acge0`[given]
`impliesb/ale0`
`acge0`
`impliesagt0,blt0,cgt0`
`or alt0,bgt0,clt0`
Promotional Banner

Similar Questions

Explore conceptually related problems

In the equations ax^(2) +bx +c=0 , if b=0 then the equations.

If one root of the equation ax^(2) + bx + c =0 is reciprocal of the one root of the equation a_(1)x^(2) + b_(1) x + c_(1) = 0 , then :

If ax^(2) +bx +c=0 has equal roots. Then c is equal to :

If the ratio of the roots of the equation a x^(2)+b x+c=0 is equal to the ratio of the roots of the equation x^(2)+x+1=0 , then a, b , c are in

In the equations ax^(2) + bx+ c =0 , if one roots is negative of the other then:

If a+b+c=0 , then the equation 3ax^(2)+2bx+c=0 has :

If ax^(2)+bx+c=0 has equal roots, 'c' is equal to

If the equation ax^(2)+bx+c=0 has equal roots, find c in terms of 'a' and 'b'.

The product of the roots of the equation x^(2) - 4 mx + 3e^(2 " log m") - 4 = 0 , then its roots will be real when m equals :

If a gt 0, b gt 0 and c gt 0 , then both the roots of the equations ax^2 + bx + c =0