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Let $\Sigma=\{a,b\}.$ Given a language $L\underline\subset \Sigma^{\ast}$ and a word $w\in\Sigma^{\ast}$, define the languages: $Extend(L,w) :=\{xw\:|\:x\in L\}$ $Shrink(L,w) :=\{x\:|\:xw\in L\}$Show that if $L$ is regular, both $Extend(L,w)$ and $Shrink(L,w)$ are regular.
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$\text{Description for the following question:}$ A golf club has $m$ members with serial numbers $1,2,\dots ,m$. If members with serial numbers $i$ and $j$ are friends, then $A(i,j)=A(j,i)=1,$ otherwise $A(i,j)=A(j,i)=0.$ By convention, $A(i,i)=0$, i.e. a person ... $A^4(1,3)=0$. Then which of the following are necessarily true? Give reasons. $m\underline> 6$
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$\text{Description for the following question:}$ A golf club has $m$ members with serial numbers $1,2,\dots ,m$. If members with serial numbers $i$ and $j$ are friends, then $A(i,j)=A(j,i)=1,$ otherwise $A(i,j)=A(j,i)=0.$ By convention, $A(i,i)=0$, i.e. a person ... $A^4(1,3)=0$. Then which of the following are necessarily true? Give reasons. $m\underline < 9$
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$\text{Description for the following question:}$ A golf club has $m$ members with serial numbers $1,2,\dots ,m$. If members with serial numbers $i$ and $j$ are friends, then $A(i,j)=A(j,i)=1,$ otherwise $A(i,j)=A(j,i)=0.$ By convention, $A(i,i)=0$, i.e. a person ... $A^2(i,i)>0$ for all $i,\;1\underline< i \underline < m.$
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$\text{Description for the following question:}$ A golf club has $m$ members with serial numbers $1,2,\dots ,m$. If members with serial numbers $i$ and $j$ are friends, then $A(i,j)=A(j,i)=1,$ otherwise $A(i,j)=A(j,i)=0.$ By convention, $A(i,i)=0$, i ... $A^4(1,3)=0$. Then which of the following are necessarily true? Give reasons. Member $1$ and member $2$ have at least one friend in common.
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. A boolean value is a value from the set {$\text{True,False}$}. A $3$-ary boolean function is a function that takes three ... $3$-ary boolean function $h$. How many neighbours does $h$ have?
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A square piece of paper $ABCD$ of side length $1$ is folded along the segment that connects the upper right corner $B$ and the midpoint $Q$ of the left edge $AD$, as shown. What is the vertical distance between the base edge (segment $DC$) and the point $P$ (which was originally point $A$)?
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$\text{Description for the following question:}$ An Ice-cream company mainly operates in the five southern states of India. The pie chart shows the breakdown of revenues (in percentages) for the ice cream company over the last summer. The bar charts shows the detail of ... sold in the same proportion across the five states, then what are the sales of chocolate in Tamil Nadu, in lakhs of rupees?
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$\text{Description for the following question:}$ An Ice-cream company mainly operates in the five southern states of India. The pie chart shows the breakdown of revenues (in percentages) for the ice cream company over the last summer. The bar chart shows the detail of breakdown for strawberry flavor by states in lakhs of rupees. What are the total sales of the chocolate flavor?
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$\text{Description for the following question:}$ An Ice-cream company mainly operates in the five southern states of India. The pie chart shows the breakdown of revenues (in percentages) for the ice cream company over the last summer. The bar chart shows the detail of breakdown for strawberry flavor by states in lakhs of rupees. What is the total revenue of the ice cream company?
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$\text{Description for the following question:}$ An Ice-cream company mainly operates in the five southern states of India. The pie chart shows the breakdown of revenues (in percentages) for the ice cream company over the last summer. The bar chart shows the detail of breakdown for strawberry flavor by states in lakhs of rupees. What are the total sales of the strawberry flavor?
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. $\text{Description for the following question:}$ Suppose $X$ is the number of successes out of $n$ ... on his/her credit than the bank loses the entire loan amount. What is the expected revenue of the bank from a loan of $Rs. 100,000?$
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. $\text{Description for the following question:}$ Suppose $X$ is the number of successes out of ... $\mathbb{E}(X)=np$. For the situation in the previous problem, what is the expected number defaults?
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. $\text{Description for the following question:}$ Suppose $X$ is the number of successes ... one credit default in a year. You can assume that whether a given debtor will default or not is independent of the behavior of other debtors.
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. A computer password requires you to use exactly $1$ uppercase letter, $3$ lowercase letters, $3$ digits and $2$ special characters (there are $33$ special characters that can be used). In how many ways can you create such a password$?$
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. A $4$-digit number is represented as $abcd$ i.e. $a\times 10^3 +b\times 10^2 +c\times10+d,$ where $a\neq0.$ Suppose the number $dcba$, obtained by reversing the digits of $abcd$, is $9$ times $abcd$. Find the number $abcd$.
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. A function $f$ from the set $A$ to itself is said to have a fixed point if $f(i)=i$ for some $i$ in $A$. Suppose $A$ is the set $\{a,b,c,d\}$. Find the number of bijective functions from the set $A$ to itself having no fixed point.
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. In computing, a floating point operation (flop) is any one of the following operations performed by a computer ... $c_{ij}=\displaystyle\sum^5 _{k=1} a_{ik} b_{kj}$. How does this number change if both the matrices are upper triangular?
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. Find $A^{10}$ where $A$ is the matrix $\begin{bmatrix} 1 & 1 & 0 \\ 0 & 1 & 1 \\ 0 & 0 & 1 \end{bmatrix}$. Justify your answer.
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. Suppose $A,B$ and $C$ are $m\times m$ matrices. What does the following algorithm compute? (Here $A(i,j)$ denotes the $(i.j)^{th}$ entry of matrix $A$.) for i=1 to m for j=1 to m for k=1 to m C(i,j)=A(i,k)*B(k,j)+C(i,j) end end end
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For numerical answers, the following forms are acceptable: fractions, decimals, symbolic e.g.:$\left( \begin{array}{c} n \\ r \end{array} \right)^n P_r , n!$ etc. Let $N=\{1,2,3,...\}$ be the set of natural integers and let $f:N\times N \mapsto N$ be defined by $f(m,n)=(2m-1)*2^n.$Is $f$ injective? Is $f$ surjective? Give reasons.
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$\text{Description of the following question:}$ The break-up of the colour of cars sold by an Indian company in a given year is provided in the pie-chart, see the Figure(1). The bar chart shows the number of grey coloured cars sold in different cities, ... of all cars were sold in Chennai. What is the largest possible percentage of brown cars sold in Chennai, rounded off to the nearest integer?
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$\text{Description of the following question:}$ The break-up of the colour of cars sold by an Indian company in a given year is provided in the pie-chart, see the Figure(1). The bar chart shows the number of grey coloured cars sold in different cities, see the Figure( ... of grey cars sold in Delhi is the same as the proportion of red cars sold in Delhi, how many red cars were sold in Delhi?
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$\text{Description of the following question:}$ The break-up of the colour of cars sold by an Indian company in a given year is provided in the pie-chart, see the Figure(1). The bar chart shows the number of grey coloured cars sold in different cities, see the Figure(2). How many blue cars were sold in that year?
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Consider the following pseudocode for a function that operates on an $N$ element array $A,A,\dots,A[N]$ of integers. function mystery (A[1...N]) { int i,j,position,tmp; for i=1 to N { position=i; for j=i+1 to N { if(A[j]<A[position]) { position=j; ... tmp; } } Explain what effect the function has on the input array $A$. If $N=100$, how many times is the comparison $A[i]<A[position]$ checked?
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A thief picks a wallet and starts running at a speed of $5\; m/s$ with zero acceleration. In $5$ seconds, a policewoman notices the alarm and starts following the thief with a speed of $3\; m/s$ with a uniform acceleration of $1\; m/s^2$. How many seconds will it take the ... velocity $v_0$ m/s and uniform acceleration $a\; m/s^2$ will cover a distance of $(at^2/2+v_0t)$ meters in $t$ seconds.)
Let $n,k$ be positive integers. The expansion of $(x_1+\dots+x_k)^n$ is given by $(x_1+\dots+x_k)^n=\sum\frac{n!}{n_1!n_2!\dots n_k!}x_1^{n_1}x_2^{n_2}\dots x_k^{n_k},$ where the sum is taken over all sequences $n_1,n_2,\dots,n_k$ of non-negative integers such that $n_1,n_2+\dots+n_k=n$. What is the coefficient of $x^5$ in the expansion of $(1+3x+2x^2)^4$?
A thin piece of metal of length $20$ cm and width $16$ cm is to be used to construct an open-topped box. A square will be cut from each corner and the sides will be folded up. What size corner should be cut so that the volume of the box is maximized?
Let $p(x)$ be a polynomial with integer coefficients. Let $n$ be a positive integer and suppse $a$ and $b$ are two integers such that $a \equiv b(\text{mod}\;n)$. Is it true that $p(a)\equiv p(b)(\text{mod}\;n)$? Justify your answer.