How many 3 digits numbers can be formed from the digits 1,2,3,4 and 5 assuming that:a. Repetitions of digits are allowed b. Repetitions of digits are not allowed[5]
2.
Define ceiling and floor function. Why do we need Inclusion - Exclusion principle? Make it clear with suitable example.[5]
Induction and Recursion
1.
State pigeonhole principle. Solve the recurrence relation an=3an−1−3an−2+an−3, with initial conditions a0=1,a1=3,a2=7.[10]
2.
Prove that for every positive integer n≥1,n2+n is even integer using mathematical induction.[5]
Integers and Matrices
1.
Find the value of x such that x = 1 (mod 3), x = 1 (mod 4), x = 1 (mod 5) and x = 0 (mod 7) using Chinese remainder theorem.[10]
2.
Define reflexive closure and symmetric closure. Find the remainder when 4x2−x+3 is divided by x + 2 using remainder theorem.[5]
Logic and Proof Methods
1.
All over smart people are stupid. Children of stupid people are naughty. John is a children of Jane. Jane is over smart. Represent these statements in FOPL and prove that John is naughty.[5]
Relations and Graphs
1.
Define Euler circuit with suitable example. Find the maximal flow s to t from the given network flow.
[10]
2.
Which of the following are possets? a. (Z,=)b. (Z,=)c. (Z,≤)[5]
3.
Define Euler path and Hamilton path. Give examples of both Euler and Hamilton path.[5]
4.
What is minimum spanning tree? Explain Kruskal's algorithm for finding minimum spanning tree.[5]
5.
List any two applications of graph coloring theorem. Prove that 'A tree with n vertices has n-1 edges'.[5]