A polynomial function with degree 1 is called a linear function.

A polynomial function with degree 2 is called a quadratic function.

This is a function but not a polynomial. The term 1/x is equal to x^-1. Since –1 is not a natural number, the function cannot be a polynomial function.

If f (x)=0 then its called a polynomial equation. Therefore the polynomial equations are equations of the form
a_nxⁿ+a_n-1x^n-1+...+a₂x²+a₁x+a₀=0

A polynomial equation is also called an algebraic equation, so this is a polynomial equation.

where a and b are real numbers and a?0. This equation is called a linear equation in one variable.

The solution set is {–b/a}

5x+5–3x–3=4 Using distribution property

2x+2=4 Re-write equation.

2x=2

x=1

So, x=1 is the solution of the equation. The solution set is denoted as {1}.

This equation is called a quadratic equation in one variable.

(x+y)²= x²+2xy+y²
(x–y)²= x²–2xy + y²
These identities are frequently used in obtaining the solutions of quadratic equations.

In the quadratic formula, b²–4ac is called the discriminant of the quadratic equation and we use
the symbol ? (capital Greek delta) for discriminant:
?= b²–4ac
If the discriminant is positive, then there are two distinct roots.If the discriminant is zero, then there is exactly one real root. If the discriminant is negative, then there are no real roots.

The graph of a function f is the collection of all ordered pairs. The graph is drawn on the Cartesian coordinate system. So, the graph has two dimensions.

An x-intercept is a point on the graph of f where y is zero and a y -intercept is a point on the graph of f where x is zero.

Mathematics has developed a useful measure for the steepness of a line, called the slope of
the line. The slope of the line through the points (x¹, y¹) and (x², y²) is
slope =Change in y/Change in x = (y² - y¹) /(x² - x¹) where x1?x2

Some lines may have slope 0. Such lines have the form y=b, and are called horizontal lines.    y=–1, y=2, etc. are examples of such lines. Horizontal lines are parallel to the x-axis.

If the line is parallel to y-axis then, it is in the form x=c and is called a vertical line.

Two lines are parallel if and only if their slopes are the same. For example, the lines y=3x–2 and
y=3x have the same slope.

Let f (x)= ax²+bx+c, a?0 be a quadratic function. The graph of f (x) is called a parabola. In what
follows we use f (x) = y (i.e. y= ax²+bx+c). Parabolas have shapes similar to a soup bowl.If the leading coefficient is positive, the parabola opens upward. If the leading coefficient is negative, the parabola opens downward. 

The vertex of the parabola is the lowest point on the graph if the graph opens upward, and the
highest point on the graph if it opens downward. The parabola is a symmetric figure and the axis
of symmetry is x=h where the vertex is (h, k).

We already know that any equation of the form y=ax+b where a?0, is a linear equation. Any of the following inequalities y>0, y?0, y<0 and y?0, is called a linear inequality.

Do not forget that the inequality symbol is reversed when the inequality is multiplied or
divided by a negative number.

For a?0, y= ax²+bx+c defines a quadratic equation. Any of the following inequalities y>0, y<0, y?0, and y?0 is called a quadratic inequality.