HARD
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If a, b, c are in GP, then the equations ax2 + 2bx + c = 0 and dx2 + 2ex + f = 0 have a common root, if da, eb, fc are in.

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Important Questions on Theory of Equation

MEDIUM
Two distinct polynomials fx and gx are defined as follows:

fx=x2+ax+2; gx=x2+2x+a

If the equations fx=0 and gx=0 have a common root then the sum of roots of the equation fx+gx=0 is
HARD
If fx=x2+ax+2=0 and gx=x2+2x+a=0 have only one real common root, then sum of the roots of fx+gx=0 is
HARD
Let bi>1 for i=1, 2,.,101. Suppose logeb1,logeb2,..,logeb101 are in Arithmetic Progression (A.P.) with the common difference loge2.  Suppose a1, a2,.,a101 are in A.P. such that a1=b1 and a51=b51. If t=b1+b2++b51 and s=a1+a2++a51, then
EASY
If the equations x 2 + 2 x + 3 = 0 and a x 2 +bx+c=0, a,b,cR, have a common root, then a:b:c is:
HARD
The quadratic equations x2-6x+a=0 and x2-cx+6=0 have one root in common. The other roots of the first and second equations are integers in the ratio 4:3. Then, the common root is
HARD
The number of real solutions of the equation sin-1i=1xi+1-xi=1x2i=π2-cos-1i=1 -x2i-i=1-xi lying in the interval -12,12 is____.

(Here, the inverse trigonometric functions sin-1x & cos-1x assume values in -π2,π2 & 0,π

respectively.)
HARD

If m is the A.M. of two distinct real numbers I and n I, n>1  and G1, G2 and G3 are three geometric means between I and n, then G14+2G24+G34 equals

MEDIUM
Suppose p, q, r are real numbers such that q=p4-p, r=q4-q, p=r4-r. The maximum possible value of p+q+r is
MEDIUM
If ax2+bx+c=0 and 2x2+3x+4=0 have a common root where a,b,cN (set of natural numbers), the least value of a+b+c is
MEDIUM
The number of pairs a,b of real numbers, such that whenever α is a root of the equation x2+ax+b=0, α2-2 is also a root of this equation, is :
MEDIUM
The sum of first 20 terms of the sequence 0.7, 0.77, 0.777, ......, is :
HARD
If the equations x2+bx-1=0 and x2+x+b=0 have a common root different from -1, then b is equal to :
MEDIUM
The sum of the 3rd and the 4th terms of a G.P. is 60 and the product of its first three terms is 1000. If the first term of this G.P. is positive, then its 7th term is:
MEDIUM
Let a, b and c be the 7th, 11th and 13th terms respectively of a non-constant A.P. If these are also the three consecutive terms of a G.P., then ac is equal to:
MEDIUM
Three positive numbers form an increasing G.P. If the middle term in this G.P. is doubled, the new numbers are in A.P. Then the common ratio of the G.P. is :
HARD
Let x,y,z be three non-negative integers such that x+y+z=10. The maximum possible value of xyz+xy+yz+zx is
MEDIUM
The quotient when 1+x2+x4+...+x34 is divided by 1+x+x2+...+x17 is
EASY
For ab, if the equation x2+ax+b=0 and x2+bx+a=0 have a common root, then the value of a+b=
HARD
Let λ0 be in R. If α and β are the roots of the equation, x2-x+2λ=0 and α and γ are the roots of the equation, 3x2-10x+27λ=0, then βγλ is equal to:
EASY
If the equations x2+ax+1=0 and x2-x-a=0 have a real common root b , then the value of b is equal to