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Consider two positive numbers a and b. If arithmetic mean of a and b exceeds their geometric mean by 32 and geometric mean of a and b exceeds their harmonic mean by 65, then the absolute value of a2-b2 is equal to :

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Important Questions on Sequence and Series

HARD
Let m be the minimum possible value of log33y1+3y2+3y3 , where y1, y2, y3 are real numbers for which y1+y2+y3=9. Let M be the maximum possible value of log3x1+log3 x2+log3 x3, where x1, x2, x3 are positive real numbers for which x1+x2+x3=9. Then the value of log2 m3+log3M2 is
HARD
Let x, y, z be positive real numbers such that x+y+z=12 and x3y4z5=0.16003. Then x3+y3+z3 is equal to
EASY
The number of three digit numbers abc¯ such that the arithmetic mean of b & c and the square of their geometric mean are equal is
HARD
Let x,y,z be positive reals. Which of the following implies x=y=z?

I. x3+y3+z3=3xyz

II. x3+y2z+yz2=3xyz

II. x3+y2z+z2x=3xyz

IV. x+y+z3=27xyz
EASY
Let I(n)=nn,J(n)=1.3.5..(2n-1) for all (n>1),nN, then
MEDIUM
Let f:RR be such that for all xR21+x+21-x, fx and 3x+3-x are in A.P., then the minimum value of fx is
HARD
If a,b,c are positive numbers such that a+b+c=1, then the minimum value of 1ab+1bc+1ca is
MEDIUM

Let n4 be a positive integer and let l1,l2,,ln be the lengths of the sides of arbitrary n sided non-degenerate polygon P. Suppose

l1l2+l2l3++ln-1ln+lnl1=n

Consider the following statements: 

I. The lengths of the sides of P are equal.
II. The angles of P are equal.
III. P is a regular polygon if it is cyclic. Then,

MEDIUM

If the arithmetic mean of two numbers a and b, a>b>0 , is five times their geometric mean, then a+ba-b is equal to:

MEDIUM
The number of different possible values for the sum x+y+z, where x, y, z are real number such that x4+4y4+16z4+64=32xyz is
HARD
The number of triples (x,y,z) of real numbers satisfying the equation x4+y4+z4+1=4xyz is
EASY
Let x and y be two positive real numbers such that x+y=1. Then the minimum value of 1x+1y is-
EASY
If a and b are arbitrary positive real numbers then the least possible value of 6a5b+10b3a is
MEDIUM
The minimum value of fx=aax+a1-ax, where a, xR and a>0, is equal to:
EASY
The minimum value of 9tan2θ+4cot2θ is _________.
EASY
If a2+b2+c2=1, then ab+bc+ca lies in the interval
MEDIUM
If three positive numbers ab and c are in A.P. such that abc=8, then the minimum possible value of b 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
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