Idea of Intervals and Signs of Inequations

IMPORTANT

Idea of Intervals and Signs of Inequations: Overview

This topic covers concepts, such as, Sign of a Quadratic Expression & Quadratic Expressions Which are Always Positive/Negative etc.

Important Questions on Idea of Intervals and Signs of Inequations

HARD
IMPORTANT

If x2+2ax+10-3a >0 for all x  R, then

EASY
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If l, ml<m are roots of ax2+bx+c=0, then limxaax2+bx+cax2+bx+c=

EASY
IMPORTANT

fx=ax2+bx+2;a,bR. If fx0;xR, then the greatest possible value of b-4a is

MEDIUM
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The following quadratic expression fx=-x2+2x-4 is always

MEDIUM
IMPORTANT

The following quadratic expression fx=2x2+4x+4 is always

MEDIUM
IMPORTANT

The quadratic equations x2-6x+4=0 has

HARD
IMPORTANT

The quadratic equations x2-5x+3=0 has

HARD
IMPORTANT

If the equation ax2+2bx-3c=0 has no real roots and 4a+b>3c, then

EASY
IMPORTANT

Find the real values of x for which (x2-4x+1) is always negative.

MEDIUM
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If am,n, then the sign of x2-(a+2)x+4 is always positive. Find the value of -m+n?

MEDIUM
IMPORTANT

Find the least integral value of k for which, k-2x2+8x+k+4>0 for all xR.

MEDIUM
IMPORTANT

If x2+2px-2p+8>0 for all real values of x then the set of all possible values of p is

MEDIUM
IMPORTANT

The exhaustive range of λ for which λx2>7x-λ,  xR , is:

HARD
IMPORTANT

For all xR, if  mx2+5m+1>9mx, then m lies in the interval _____

HARD
IMPORTANT

If α  R- and α2x2+8x+α+4<0,xR, then α cannot be ____

HARD
IMPORTANT

Consider the quadratic equation: x2-24k-1x+15k2-2k-7>0   x ϵ R .Find the integral value of k

EASY
IMPORTANT

The values of a such that  a2-1x2+2a-1x+2 is positive for any x is

MEDIUM
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Find the number of integral values of k for which x2-2(4k-1)x+15k2-2k-70 hold for all real x.

MEDIUM
IMPORTANT

Find least integral value of k such that (k-2)x2+8x+k+4 is positive for all real values of x.

HARD
IMPORTANT

Find the largest integral value of m for which the quadratic expression y=x2+2m+4x+7m+8 is positive for all xR