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We need to find the zeros here, and we realize based on the
graph that negative 12345 and six -6 is going to be a
solution.
This tells us our farthest to the left X, our farthest to the
right X, and what we're counting by our farthest to the left well
down Y, our highest Y, and what we're counting our YS by.
So we know that -6 is going to work if we use synthetic
division 9/24 negative 1:55 and 1:50.
So we always bring down our first number.
If we're below the line, we multiply.
If we're above the line, we're going to add.
If we're below the line, we're going to multiply.
If we're above the line, we're going to add.
If we're below the line, we're going to multiply.
Above the line, we're going to add.
So this gives us a new polynomial.
So we know that X + 6 * 9 X squared minus thirty X + 25
equals the F of X.
When we took out the -6, it's always X minus the root, and
this nine had to be one root smaller.
So if it's an X cube, we knew it had to start with an X ^2.
Now we're going to see if this can factor.
If it can't factor, we're going to use quadratic formula.
SO3X times 3X is nine X ^2 -5 * -5 gives me the +25.
And if we do the outer term of -15 X and the inner term of -15
X, that gives us negative 30X.
So we see that our solutions are -6 and 5 thirds.
So when we think about graphing this, we have a -6 here and we
have a 5 thirds here and the leading coefficients positive.
So we're going to come down to this first intercept, three X -,
5 * 3 X -5.
So that's really a degree of two because that root occurs twice.
So if the YS on one side are positive, the YS on the other
side are going to be positive.
We come to the next zero, and at the next zero, it's -6.
The degree for that is odd.
It's one multiplicity.
So if the YS on one side are positive, the YS on the other
side have to be negative.
So our rough sketch is going to be graph A in this example.