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You are given the equation $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$. 

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The equation $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$, or its graph, can be described as a

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An equation of the form $y=ax^4+bx^3+cx^2+dx+e$ is known as a quartic, or a quartic polynomial. If we expand $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$ we will see it is a quartic.

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straight line

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parabola/quadratic

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cubic

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hyperbola

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circle

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quartic

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As we move to the far left of the graph of $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$, the graph

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What happens to the graph as you go far to the left or right is called the long term behaviour of a graph.

\n

The leading term (the term that includes the highest power) determines the long term behaviour of a polynomial.

\n

By expanding $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$ we see that the leading term is $\\simplify[all,fractionNumbers]{{a}x^4}$. 

\n

As we go far to the left of the graph $x$ is negative, and so $\\simplify[all,fractionNumbers]{{a}x^4}$ is negative. That is, the graph goes downwards. is positive. That is, the graph goes upwards. 

\n

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goes upwards.

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goes downwards.

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As we move to the far right of the graph of $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$, the graph

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What happens to the graph as you go far to the left or right is called the long term behaviour of a graph.

\n

The leading term (the term that includes the highest power) determines the long term behaviour of a polynomial.

\n

By expanding $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$ we see that the leading term is $\\simplify[all,fractionNumbers]{{a}x^4}$. 

\n

As we go far to the right of the graph $x$ is positive, and so $\\simplify[all,fractionNumbers]{{a}x^4}$  is negative. That is, the graph goes downwards. is positive. That is, the graph goes upwards. 

\n

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goes upwards.

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goes downwards.

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The $y$-intercept of the graph of $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$ is $y=$[[0]].

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The $y$-intercept is the value of $y$ when $x=0$, that is, the value of $y$ where the graph hits the $y$-axis. To find it, substitute $x=0$ into our equation:

\n

\\[y=\\simplify[unitFactor,basic,fractionNumbers]{(0-{ee})(0-{d})({a}0^2+{b}0+{c})}=\\var{yint}.\\]

\n

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The set of $x$-intercepts of the graph of $y=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})}$ would be [[0]].

\n

Note: If there are no intercepts, enter set()

\n

If there is only one intercept, say $x=5$, enter set(5)

\n

If there are two intercepts, say $x=-2$ and $x=1.5$, enter set(-2,1.5)

\n

If there are three intercepts, say $x=-2$, $x=1.5$ and $x=5$, enter set(-2,1.5,5)

\n

etc

\n

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The $x$-intercept is the value of $x$ when $y=0$, that is, the value of $x$ where the graph hits the $x$-axis. To find it, substitute $y=0$ into our equation:

\n

\\[0=\\simplify[all,fractionNumbers]{(x-{ee})(x-{d})({a}x^2+{b}x+{c})} \\]

\n

Recall, if a product is zero then one of the factors must be zero, therefore

\n

\\[\\simplify[all,fractionNumbers]{x-{ee}=0}\\quad \\textrm{or}\\quad\\simplify[all,fractionNumbers]{x-{d}=0}\\quad \\text{or}\\quad\\simplify[all,fractionNumbers]{{a}x^2+{b}x+{c}=0}.\\]

\n

Solving the first equation says that one of the $x$-intercepts is $x=\\var{ee}$.

\n

Solving the second equation says that one of the $x$-intercepts is $x=\\var{d}$.

\n

For the third equation we will use the quadratic formula. Recall for $ax^2+bx+c=0$, the solutions (if they exist) are given by \\[x=\\dfrac{-b}{2a}\\pm\\dfrac{\\sqrt{b^2-4ac}}{2a}.\\]

\n\n

For the equation $y=\\simplify[all,fractionNumbers]{{a}x^2+{b}x+{c}}$, we have $b^2-4ac=\\simplify[all,fractionNumbers]{{b}^2-4{a}{c}}=\\var{disc}$ and so there are no more $x$-intercepts. is one more $x$-intercept: are two more $x$-intercepts: 

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
$x$$=$$\\dfrac{-b}{2a}\\pm\\dfrac{\\sqrt{b^2-4ac}}{2a}$
 
$=$$\\simplify[basic,unitFactor,fractionNumbers]{{axis_x}}\\pm\\simplify[basic,unitFactor,fractionNumbers]{sqrt{{disc}}/({2*a})}$
 
$=$$\\var{axis_x}$  $\\var{xint0}, \\, \\var{xint1}$
\n

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Given the degree of a polynomial is $4$, the maximum number of possible 'bends' or 'turns' in the graph is [[0]].

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A degree $n$ polynomial has at most $n-1$ bends in its graph.

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