Prove that the numbers of the sequence `121, 12321,1234321, ........... ` are each a perfect square of odd integer.

The number which is not a perfect square is-

The number of positive integers n such that n+9,16n+9,27n+9 are all perfect squares is

What is the vaue of sqrt 121 + sqrt 12321 + sqrt 1234321 + sqrt 123454321

Prove that the sum of the numbers in any group in the following is the square of an odd integer: (1),(1, 3, 5),(1, 3, 5, 7, 9),... .

Number of natural numbers n>=10 for which the expression P(n)=^(n)C_(10)*^(n+1)C_(10) is a perfect square of an integer?

The square of an odd integer must be of the form:

Find the smallest number by which 1100 must be multiplied so that the product becomes a perfect square.Also in each find the square root of the perfect square so obtained.