MHF 4UI-Polynomial Functions A function is a relationship between two sets of numbers in which each value of x, in the ________________, corresponds to exactly one value of y, in the __________________. f(x) is called function notation and represents the y value of the function for some given value of x. Polynomial Functions: A polynomial function is a function whose equation is defined by a polynomial in one variable. f ( x) a n x n a n 1 x n 1 a n 2 x n 2 ... a 2 x 2 a1 x a0 where a0 , a1 , a 2 ,...a n are real numbers and n is a natural number. The coefficient of the highest term is called the __________________________. The ___________ of the polynomial function is the value of the highest exponent of the variable. A ____________ function, f ( x) ax b , is a polynomial function of degree____________. A ____________ function, f ( x) ax 2 bx c , is a polynomial function of degree________. A __________ three polynomial function , f ( x) ax 3 bx 2 cx d , is called_____________. Increasing and Decreasing Functions A function f, is increasing on an interval I if the value of f(x) increases as the value of x increases. f ( x1 ) f ( x2 ) when x1 x2 and x1 and x2 are in I. A function f, is decreasing on an interval I if the value of f(x) decreases as the value of x increases. f ( x1 ) f ( x2 ) when x1 x2 and x1 and x2 are in I. Local Minimum and Local Maximum values A turning point is a point on a curve that is higher or lower than all nearby points. A turning point occurs wher a function Changes from increasing to decreasing or vica versa. A local ____________ occurs when the function changes from increasing to decreasing. A local _____________ occurs when the function changes from decreasing to increasing. Zeros of a Polynomial Function The zeros of a function are the ___________________, and can easily be found when the polynomial function is in __________ form. If k represent the leading coefficient; the linear function f ( x) k ( x s ) has a zero ___; the quadratic function f ( x) k ( x s)( x t ) has zeros ________; the cubic function f ( x) k ( x s)( x t )( x u ) has zeros _____________. [s,t and u can be any real value] End Behaviour of a Polynomial Function An important property of a function is its end behaviour. As x takes on a very large positive value “ x ” and as x takes on a very large negative value “ x ” we observe the values of the function f(x) get larger in a positive or negative direction. 6 As x f(x) gets larger in a negative direction _____________. 4 2 -10 -5 5 10 As x f(x) gets larger in a positive direction _____________. -2 -4 -6 Even and odd functions A function is an even function if f(-x) = f-x) for all values of x. An even function is symmetrical about the ___________. A function is odd if f(-x) = -f(x) for all value of x. An odd function is symmetrical about the _________. Note: There are functions which are neither even nor odd. Finite Differences in Polynomial Functions The nth finite differences of a polynomial function of degree ___ are ________. The third finite difference of a degree - _______ polynomial is related to the leading coefficient by a factor of __________________. The fourth finte difference of a degree-_________ polynomial is related to the leading coefficient by a factor of ____________________.