HARD
Earn 100

If a,b,c are distinct numbers in arithmetic progression, then both the roots of the quadratic equation a+2b-3cx2+b+2c-3ax+c+2a-3b=0 are

50% studentsanswered this correctly

Important Questions on Theory of Equation

HARD
The houses on one side of a road are numbered using consecutive even numbers. The sum of the numbers of all the houses in that row is 170. If there are at least 6 houses in that row and a is the number of the sixth house, then
HARD
Let α  and  β be the roots of equation px2+qx+r = 0, p0. If p, q, r are in A.P. and 1 α + 1 β = 4 , then the value of α - β is 
HARD
For any three positive real numbers a, b and c. If 925a2+b2+25c2-3ac=15b3a+c. Then
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

HARD
Let X be the set consisting of the first 2018 terms of the arithmetic progression 1,6,11, , and Y be the set consisting of the first 2018 terms of the arithmetic progression 9,16,23,  . Then, the number of elements in the set XY is___.
HARD
Let Sn=Σk=14n-1kk+12k2. Then Sn can take value(s)
MEDIUM
Let 1x1, 1x2,,1xn(xi0 for i=1, 2,., n) be in A.P. such that x1=4 and x21=20 . If n is the least positive integer for which xn>50, then i=1n1xi is equal to
HARD
Given an A.P. whose terms are all positive integers. The sum of its first nine terms is greater than 200 and less than 220.  If the second term in it is 12, then its 4th term is :
MEDIUM
If x, y, z are positive numbers in A.P. and tan-1xtan-1y and  tan-1z are also in A.P., then which of the following is correct.
HARD
Let the sum of the first three terms of an A.P. be 39 and the sum of its last four terms be 178. If the first term of this A.P. is 10, then the median of the A.P. is :
MEDIUM
If the sum of the first n terms of the series 3+ 75+ 243+ 507+ is 4353, then n equals:
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
If a1/x=b1/y=c1/z and a,b,c are in geometrical progression, then x,y,z are in
HARD
Let a, b, c, d, e be natural numbers in an arithmetic progression such that a+b+c+d+e is the cube of an integer and b+c+d is a square of an integer. The least possible value of the number of digits of c is
HARD
The number of terms in an A.P. is even, the sum of the odd terms in it is 24 and that the even terms is 30. If the last term exceeds the first term by 1012, then the number of terms in the A.P. is 
MEDIUM
Let a1, a2, a3,an, ,be in A.P. If a3+a7+a11+a15=72, then the sum of its first 17 terms is equal to :
MEDIUM
Let a1, a2, a3,,a49 be in A.P. such that Σ k = 0 1 2 a4k+1=416 and a9+a43=66. If a12+a22++a172=140m, then m 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
If nC4, nC5 and nC6 are in A.P., then n can be
MEDIUM
The sum of all two digit positive numbers which when divided by 7 yield 2 or 5 as remainder is