Home
Class 12
MATHS
If a, b, c are positive numbers such tha...

If `a`, `b`, `c` are positive numbers such that `a gt b gt c` and the equation `(a+b-2c)x^(2)+(b+c-2a)x+(c+a-2b)=0` has a root in the interval `(-1,0)`, then

A

`b` cannot be the `G.M.` of `a`,`c`

B

`b` may be the `G.M.` of `a`,`c`

C

`b` is the `G.M.` of `a`,`c`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
A

`(a)` Let `f(x)=(a+b-2c)x^(2)+(b+c-2a)x+(c+a-2b)`
According to the given condition, we have
`f(0)f(-1) lt 0`
`implies (c+a-2b)(2a-b-c) lt 0`
`implies (c+a-2b)(a-b+a-c) lt 0`
`implies c+a-2b lt 0`
[`a gt b gt c`, given `implies a-b gt 0`, `a-c gt 0`]
` b gt (a+c)/(2)`
`impliesb` cannot be the `G.M.` of `a`, `c`, since `G.M lt A.M.` always.
Promotional Banner

Topper's Solved these Questions

  • THEORY OF EQUATIONS

    CENGAGE|Exercise Comprehension|12 Videos
  • THEORY OF EQUATIONS

    CENGAGE|Exercise Multiple Correct Answer|6 Videos
  • STRAIGHT LINES

    CENGAGE|Exercise JEE Advanced Previous Year|4 Videos
  • THREE DIMENSIONAL GEOMETRY

    CENGAGE|Exercise Question Bank|12 Videos

Similar Questions

Explore conceptually related problems

If the equation (b^2 + c^2) x^2 -2 (a+b) cx + (c^2 + a^2) = 0 has equal roots, then

The roots of the equation a(b-2c)x^(2)+b(c-2a)x+c(a-2b)=0 are, when ab+bc+ca=0

Let a, b and c be real numbers such that 4a + 2b + c = 0 and ab gt 0. Then the equation ax^(2) + bx + c = 0 has

If a b+b c+c a=0, then solve a(b-2c)x^2+b(c-2a)x+c(a-2b)=0.

If a,b and c are distinct positive real numbers in A.P, then the roots of the equation ax^(2)+2bx+c=0 are

if a lt c lt b, then check the nature of roots of the equation (a -b)^(2) x^(2) + 2(a+ b - 2c)x + 1 = 0

If 2a+3b+6c=0, then prove that at least one root of the equation a x^2+b x+c=0 lies in the interval (0,1).

If the roots of the equation a(b-c)x^2+b(c-a)x+c(a-b)=0 are equal, show that 2//b=1//a+1//c dot

The quadratic equation (x-a)(x-b)+(x-b)(x-c)+(x-c)(x-a)=0 has equal roots if

If the roots of (a-b)x^(2)+(b-c)x+(c-a)=0 are equal, prove that 2a=b+c .