6. Let R be a relation on Z x Z such that for all ordered pairs...
6. Let R be a relation on Z x Z such that for all ordered pairs
(a, b),(c, d) ∈ Z x Z, (a, b) R (c, d) ⇔ a ≤ c and b|d . Prove that
R is a partial order relation.
Is the relation R consisting of all ordered pairs (a, b) such
that a and b are people and have one common parent: reflexive,
irreflexive, symmetric, antisymmetric, asymmetric, and/or
transitive? If a property doesn’t hold give a counter-example and
state the logical definitions of the properties as you consider
them.
Let R be the relation on Z+× Z+ such that (a, b) R (c, d) if and
only if ad=bc. (a) Show that R is an equivalence relation. (b) What
is the equivalence class of (1,2)? List out at least five elements
of the equivalence class. (c) Give an interpretation of the
equivalence classes for R. [Here, an interpretation is a
description of the equivalence classes that is more meaningful than
a mere repetition of the definition of R. Hint:...
Let A = R x R, and let a relation S be defined as: “(x1, y1)
S (x2, y2) ⬄ points (x1, y1) and (x2, y2)are 5 units
apart.” Determine whether S is reflexive, symmetric, or transitive.
If the answer is “yes,” give a justification (full proof is not
needed); if the answer is “no” you must give a
counterexample.
Let S = {2 k : k ∈ Z}. Let R be a relation defined on Q− {0} by
x R y if x y ∈ S. Prove that R is an equivalence relation.
Determine the equivalence class
Let S be the set of all ordered pairs of real numbers. Define
scalar multiplication and addition on S by:
α(x1,x2)=(αx1,αx2)
(x1,x2)⊕(y1,y2)=(x1 +y1,0)
We use the symbol⊕to denote the addition operation for this
system in order to avoid confusion with the usual addition x+y of
row vectors.
Show that S, together with the ordinary scalar multiplication
and the addition operation⊕, is not a vector space.
Test ALL of the eight axioms and report which axioms
fail to hold.
Let V be the set of all ordered pairs of real numbers. Consider
the following addition and scalar multiplication operations V. Let
u = (u1, u2) and v = (v1, v2).
Show that V is not a vector space.
• u ⊕ v = (u1 + v1 + 1, u2 + v2 + 1 )
• ku = (ku1 + k − 1, ku2 + k − 1)
1)Show that the zero vector is 0 = (−1, −1).
2)Find the...
6. (a) let f : R → R be a function defined by
f(x) =
x + 4 if x ≤ 1
ax + b if 1 < x ≤ 3
3x x 8 if x > 3
Find the values of a and b that makes f(x) continuous on R. [10
marks]
(b) Find the derivative of f(x) = tann 1
1 ∞x
1 + x
. [15 marks]
(c) Find f
0
(x) using logarithmic differentiation, where f(x)...