When you need to graph a radical function with multiple transformation it is important to know the different types of transformations. In this video I will help you identify the transformations and how to eliminate them.
right something I tell my students all
the time whenever you're having a b in
front or any kind of number in front of
your ex inside of your function you got
to factor that number out see what we're
trying to do is we're trying to get our
function in this form this is going to
be a times square root of B times x
minus C
plus d so we want our coefficient of x
to be one you can see right now our
coefficient is two-thirds and so what we
need to do then the most common way to
be able to factor it out or to rewrite
an expression as a product multiplying
is to factor how do you factor out a
two-thirds I think it's pretty easy when
you say like 2 2x plus 4. it's like how
do you factor it out when you say oh
they have in common of two so you factor
out the 2 right X plus two and you're
like okay good like I know how to factor
and you can always check your work right
multiply it back out and you get a 2X
plus 4. how the heck do you factor out
of two-thirds because I don't know what
two-thirds basically goes into there
let's go and take a look at a different
way that we can do this so I have a
two-thirds X Plus One how can I factor
out the two thirds well a lot of times
when you're thinking about factoring it
can be overwhelming because you're like
I don't know what they have in common
like what is a two-thirds and a one have
in common that I can factor out so then
it kind of brings it to the point of
like well technically when you're
factoring out what exactly are you doing
we said we're taking out the common
factor of two but what exactly does that
mean if you look at this basically what
I'm doing is I'm taking a 2X dividing it
by 2 to give me X I'm taking a 4 divided
by 2 and and that's given me a two so
I'm taking whatever number I'm dividing
both of these terms by I'm putting it on
the outside all right so two-thirds
whenever I divide that number so when I
take that term divided by two whatever
is left over I'm going to put inside
this parenthesis so let's go and do this
2 3 x divided by two-thirds well that's
just going to be an X this one might be
a little confusing what is 1 divided by
two-thirds but there are some things you
do know so let's go and take a look at
that if I have one divided by two thirds
you recognize they're like oh yeah you
can't divide by fractions right you need
to get rid of your fraction you multiply
by the reciprocal
so you multiply by three halves on both
sides so therefore that goes to one so
you have a three halves divided by one
which is just going to be a three-halves
so therefore this is X plus a
three-halves and if you think about it
guys that actually makes sense because
when you multiply back out right
remember how we multiply this 2 times x
is 2x 2 times 2 is 4. when you multiply
this back over you have a two-thirds
times x which is a two-thirds X you
multiply two-thirds times a three-half
those are reciprocals of each other
that's going to give you back to a one
now way to rewrote this I also don't
like having my D in front sometimes
you'll see that a lot in textbooks or on
math problems let's go and put that out
there right I like having my D here
remember there was no addition or
subtraction sign in front of the one but
therefore if there's nothing in front of
it we can assume that our presume that
is going to be a positive because
obviously if I had a negative in front
of it it would be represented as a
negative so now I don't want you to see
here is we have a lot of operation we
have a reflection on the outside so
therefore if it's a vertical reflection
that's going to be a reflection about
the x-axis we have a vertical shift up
one then inside here we have a
horizontal let's see if it's less than
between 0 and 1 it's going to be a
horizontal stretch so we have a
horizontal stretch of two-thirds as well
as a horizontal shift of three halves
what are we going to graph first well
the main important thing that I want you
to understand is the way I like to do
this is I like to break this apart in
two parts
the first part is going to be the
orientation
all right what I want to do is I want to
know all right where is this graph going
so we know that the y equals the square
root of x looks like this
okay so now What's Happening Here is
this graph is being reflected about the
x-axis right so now it's so take this
graph it's being reflected about the
x-axis and then we're having a
horizontal stretch of two-thirds so I'm
not going to be exact here guys I'm just
going to say all right it's going to be
horizontal stretch so it's going to be a
little bit skinnier or something like
that right all right the next one the
next step is going to be the
translations
that is going to be everything left and
right so you can see here we're going to
be shifting it left three halves and
then up one so all I'm simply going to
do here so if I'm going to go by ones
right we're going left three halves so
that's one and one half right so one and
one half and then we're going to go up
one
so it's right there so what I'm doing is
I'm basically just taking this
coordinate point which is at zero zero
I'm shifting it left one and one half
going up one and then I'm just gonna
like basically copy paste my translation
here to go ahead and do this and let's
say
you know look something like that now we
can identify the domain and range
because again this is very very
important to recognize how far left is
this graph well that's going to be at a
negative three halves how high is this
graph right well that's at a one
the reason why that's important is
because when I want to identify my
domain and range let's actually and let
me graph this so
so you just make sure you go from there
and then you shift it left to right all
right so let's go and figure out my
domain is domain is going to be
basically how far left the graph is
going which in this case is going to be
a negative three halves how far to the
right it's going which is going to be a
positive infinity and then the range is
going to be basically how low does the
graph go which is going to be from
negative Infinity to how high is it
going to go which is going to be a
positive one hopefully this video
brought you some value in being able to
identify the Transformations and grab it
and if so I know the next video is going
to give you value as well cheers