Quiz-A
#1.- (following Cantor) What are the fundamental concepts of Mathematics?
a) positive and negative numbers.
b) fear, uncertainty and doubt.
c) sets, elements and logic.
d) real numbers and real functions.
#2.- Let and let
be a function from P
to ℤ defined as:
.
a) Is one-to-one? if the answer is “no” , Produce a “witness”.
No
Witness: {3} and {1,2}
b) Is onto?
No
Witness: No element of P(A) maps to integer 100
#3.- Let : ℤ
ℤ be defined as
a) Is one-to-one?
No
Witness: g(1) = g(-1).
b) Is onto?
No
Witness: there is no value of x for which g(x) = -4
#4.- According to the laws of logarithms
logxa - logxb