1
GATE CSE 2009
MCQ (Single Correct Answer)
+1
-0.3
consider the binary relation $$R = \left\{ {\left( {x,y} \right),\,\left( {x,z} \right),\,\left( {z,x} \right),\,\left( {z,y} \right)} \right\}$$ on the set $$\left\{ {x,\,y,\,z} \right\}$$. which one of the following is TRUE?
A
$$R$$ is symmetric but $$NOT$$ antisymmetric
B
$$R$$ is NOT symmetric but antisymmetric
C
$$R$$ is both symmetric and antisymmetric.
D
$$R$$ is neither symmetric nor antisymmetric.
2
GATE CSE 2009
MCQ (Single Correct Answer)
+2
-0.6
For the compositive table of a cyclic group shown below GATE CSE 2009 Discrete Mathematics - Set Theory & Algebra Question 38 English

Which one of the following choices is correct?

A
a, b are generators
B
b, c are generators
C
c, d are generators
D
d, a are generators
3
GATE CSE 2009
MCQ (Single Correct Answer)
+2
-0.6
Consider the following well-formed formulae:

$${\rm I}.$$ $$\,\,\neg \forall x\left( {P\left( x \right)} \right)$$
$${\rm I}{\rm I}.\,\,\,\,\,\,\neg \exists x\left( {P\left( x \right)} \right)$$
$${\rm I}{\rm I}{\rm I}.\,\,\,\,\,\,\neg \exists x\left( {\neg P\left( x \right)} \right)$$
$${\rm I}V.\,\,\,\,\,\,\exists x\left( {\neg P\left( x \right)} \right)$$

Which of the above are equivalent?

A
$${\rm I}$$ and $${\rm I}$$$${\rm I}$$
B
$${\rm I}$$ and $${\rm I}$$$$V$$
C
$${\rm I}$$$${\rm I}$$ and $${\rm I}$$$${\rm I}$$$${\rm I}$$
D
$${\rm I}$$$${\rm I}$$ and $${\rm I}$$$$V$$
4
GATE CSE 2009
MCQ (Single Correct Answer)
+2
-0.6
Which one of the following is the most appropriate logical formula to represent the statement:

"$$Gold\,and\,silver\,ornaments\,are\,precious$$"

The following notations are used:
$$G\left( x \right):\,\,x$$ is a gold ornament.
$$S\left( x \right):\,\,x$$ is a silver ornament.
$$P\left( x \right):\,\,x$$ is precious.

A
$$\forall x\left( {P\left( x \right) \to \left( {G\left( x \right) \wedge S\left( x \right)} \right)} \right)$$
B
$$\forall x\left( {\left( {G\left( x \right) \wedge S\left( x \right)} \right) \to P\left( x \right)} \right)$$
C
$$\exists x\left( {\left( {G\left( x \right) \wedge S\left( x \right)} \right) \to P\left( x \right)} \right)$$
D
$$\forall x\left( {\left( {G\left( x \right) \vee S\left( x \right)} \right) \to P\left( x \right)} \right)$$