Answer:
Step-by-step explanation:
As the statement is ‘‘if and only if’’ we need to prove two implications
is surjective implies there exists a function
such that
.- If there exists a function
such that
, then
is surjective
Let us start by the first implication.
Our hypothesis is that the function
is surjective. From this we know that for every
there exist, at least, one
such that
.
Now, define the sets
. Notice that the set
is the pre-image of the element
. Also, from the fact that
is a function we deduce that
, and because
the sets
are no empty.
From each set
choose only one element
, and notice that
.
So, we can define the function
as
. It is no difficult to conclude that
. With this we have that
, and the prove is complete.
Now, let us prove the second implication.
We have that there exists a function
such that
.
Take an element
, then
. Now, write
and notice that
. Also, with this we have that
.
So, for every element
we have found that an element
(recall that
) such that
, which is equivalent to the fact that
is surjective. Therefore, the prove is complete.
Answer:
the answer is 59048
Step-by-step explanation:
as the common ratio is multiplying by 3 and the first term is 1 so from the rule (Tn=ar(power n-1 ) )
so the 11th term is 1*3(power 11-1 ) equal 3 power 10 equal 59048
Answer:
I could try.
Step-by-step explanation:
Answer:
Dans 3 ans l’âge du père sera le triple de celui de sa fille
Step-by-step explanation:
X= années qui doivent passer
3(12+X ) = 42 +X
36+ 3X = 42 +X
2X = 6
X = 3
La fille 15 ans
Le père 45 ans (15x3=45)
A term can be a signed number, a variable, or a constant multiplied by a variable or variables. Each term in an algebraic expression is separated by a + sign or J sign. ... When a term is made up of a constant multiplied by a variable or variables, that constant is called a coefficient.