Recent questions tagged isi2016

0 votes
1 answer
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3 votes
4 answers
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If $a,b,c$ and $d$ satisfy the equations$a+7b+3c+5d =16$$8a+4b+6c+2d = -16$$2a+6b+4c+8d = 16$$5a+3b+7c+d= -16$Then $(a+d)(b+c)$ equals$-4$$0$$16$$-16$
15 votes
3 answers
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Consider all possible trees with $n$ nodes. Let $k$ be the number of nodes with degree greater than $1$ in a given tree. What is the maximum possible value of $k$?
11 votes
3 answers
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Let $A$ be a matrix such that:$A=\begin{pmatrix} -1 & 2\\ 0 & -1 \end{pmatrix}$and $B=A+A^2+A^3+\ldots +A^{50}$. Then which of the following is true?$B^{2}=I$$B^{2}=0$$B^...
6 votes
3 answers
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Find the number of positive integers n for which $n^{2}+96$ is a perfect square.
19 votes
4 answers
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A palindrome is a sequence of digits which reads the same backward or forward. For example, $7447$, $1001$ are palindromes, but $7455$, $1201$ are not palindromes. How ma...
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