# Questions by dhairya

1
(P + Q’) (PQ’ + PR) (P'Q’+PR) (P’R’ + Q’) simplifies to (A) PQ’ (B) PQ’+ R (C) PR’ (D) PR’ + Q
1 vote
2
A probability density function density function is of form P(x)= k e ^(-a |x|) , the value of k is A)0.5 B)1 C) 0.5 a D) a
1 vote
3
1 vote
4
a = b + " cde " ; Which phase of compiler will give error ?
5
S-> AB / Ɛ A-> AC / 0C B->0S C->1 What is the first (A)..??
6
Find first and follow... S→ABa / bCA A→cBCD / є B→CdA / ad C→eC / є D→bsf / a
1 vote
7
Consider 3 relation R(A, B, C) WITH 20 TUPLES and S(A,D , E) With 30 tuples and T(D,F,G ) with 40 tuples. What is the max no. of tuples in natural joint of R S T Plz explain
8
Consider the following C function: int f(int n) { static int r = 0; If (n < = 0) return 1; If (n > 3) { r = n; return f (n &ndash; 2) + 2; } return f(n &ndash; 1) + r; } What is the value of f(5)? (A) 3 (B) 7 (C) 9 (D) 18
1 vote
9
Let S be a stack of size n ≥ 1. Starting with the empty stack, suppose we Push the first n natural numbers in sequence, and then perform n Pop operations. Assume that Push and POP operations take X seconds each, and Y seconds elapse between the end of one such stack operation and the start of the next operation. ... an element of this stack is (A) n(X + Y) (B) 3Y + 2X (C) N(X + Y) - X (D) Y + 2X
10
A circularly linked list is used to represent a Queue. A single variable pp is used to access the Queue. To which node should pp point such that both the operations are EnQueue and DeQueue enQueue deQueue can be performed in constant time? rear node front node not possible with a single pointer node next to front What does "constant time" means...(last words of the question).?
11
12
Consider the following ER diagram: If A has 100 entities, B has 1000 entities, and C has 10 entities, what is the maximum number of triples of entities that could be in the relationship set for R?
13
Consider the following F.D. ab -> cd ; e->c ; b->ef Which options show the relations normalized to 3NF of R(A,B,C,D,E,F) 1) R(A,B,C,D) , R(C,E) , R(E,F,B) 2) R(A,B,D) , R(E,C) , R(B,E,F) 3) R(A,B,C,D) , R(C,E) , R(B,E,F) 4) R(A,B,C,D,E,F) , R(E,C) , R(B,E,F) Ans is C
14
R(A,B,C,D) is a relation. Which of the following does not have a lossless join, dependency preserving BCNF decomposition? a)A->B, B->CD b)A->B, B->C, C->D c) AB->C, C->AD d)A ->BCD Plz explain as well...!!!!
15
R (A, B, C ,D ,E ) F={ A->B, BC-> D, D->BC, B->E, B->A } Check whether BD is C.Key or S.key . Also find the candidate key.
16
R ( A, B, C, D) A & B are the candidate keys . what are the possible Super keys and there no ..??
17
R (A, B, C) Functional dependency= { A -> B, B -> C , C -> A } No of super keys are...??
Find the cardinality of --- 1) $\phi$ 2) { $\phi$} 3) { $\phi$ , { $\phi$} } 4) { $\phi$, { $\phi$} , { $\phi$, { $\phi$ } } }