Showing posts with label Polynomial Functions. Show all posts
Showing posts with label Polynomial Functions. Show all posts

Determining Polynomial Functions

Introduction about polynomial:

In mathematics, a polynomial is an expression of finite length constructed from variables (also known as indeterminate) and constants, using only the operations of addition, subtraction, multiplication, and non-negative, whole-number exponents. For example, x2 - 4x + 7 is a polynomial, but x2 - 4/x + 7x3/2 is not, because its second term involves division by the variable x and because its third term contains an exponent that is not a whole number. (Source: Wikipedia)

Example Problems for Determining Polynomial Functions :

Determining polynomial functions - Example problem 1:

Simplify f(x) = (21x + 15y) + ( 9x – 21y ) – (11x – 17y)

Solution:

f(x) = (21x + 15y) + ( 9x – 21y ) – (11x – 17y) = 21x + 15y + 9x – 21y – 11x + 17y

= 21x + 9x - 11x + 15y – 21y + 17y

= 19x +11y

The answer for f(x) = (21x + 15y) + ( 9x – 21y ) – (11x – 17y) = 19x + 11y

Determining polynomial functions - Example problem 2:

Simplify f(x) = (15x^2 – 11x – 21) + (7x^2 – 16x – 19) - (–7x^2 + 5x + 21)

Solution:

(15x^2 – 11x – 21) + (7x^2 – 16x – 19) - (–7x^2 + 5x + 21)

= 15x^2 – 11x – 21 + 7x^2 – 16x – 19 + 7x^2 - 5x - 21

= 15x^2 + 7x^2 + 7x^2 – 11x – 16x - 5x – 21 – 19 - 21

= 29x^2– 36x – 61

The answer for f(x) = (15x^2 – 11x – 21) + (7x^2 – 16x – 19) - (–7x^2 + 5x + 21) = 29x^2– 36x – 61

Determining polynomial functions - Example problem 3:

Simplify f(x) = (14x3 + 8x^2 + 21x – 16) – (18x3 – 15x^2 – 7x + 17) - (8x^2 – 11x – 21)

Solution:

(14x3 + 8x^2 + 21x – 16) – (18x3 – 15x^2 – 7x + 17) - (8x^2 – 11x – 21)

= (14x3 + 8x^2 + 21x – 16) – 1(18x3 – 15x^2 – 7x + 17) – 1(8x^2 – 11x – 21)

= (14x3 + 8x^2 + 21x – 16)– 1(18x3) – 1 (–15x^2) – 1(–7x) – 1(17) - 1(8x^2) -1(-11x) -1(-21)

= 14x3 + 8x^2 + 21x – 16 – 18x3 + 15x^2 + 7x – 17 - 8x^2 + 11x + 21

= 14x3 – 18x3 + 8x^2 + 15x^2 -8x^2 + 21x + 7x + 11x – 16– 17 + 21

= -4x3 + 15x^2 + 39x –20

The answer for f(x) = (14x3 + 8x^2 + 21x – 16) – (18x3 – 15x^2 – 7x + 17) - (8x^2 – 11x – 21) = -4x3 + 31x^2 + 39x –20

Practice Problems for Determining Polynomial Functions :

1. Simplify f(x)= (15x + 8y) + ( 7x – 15y ) – (8x – 9y)

The answer for f(x)= (15x + 8y) + ( 7x – 15y ) – (8x – 9y) = 14x + 2y

2. Simplify f(x)= (7x^2 – 9x – 8) + (3x^2 – 8x – 11) - (–6x^2 + 9x + 15)

The answer for f(x)=(7x^2 – 9x – 8) + (3x^2 – 8x – 11) - (–6x^2 + 9x + 15)= 16x^2– 26x – 34