How do you write a polynomial in standard form, then classify it by degree and number of terms #3k^5+4k^2-6k^5-5k^2#?

1 Answer
Mar 22, 2016

standard form: #-3k^5-k^2=0#
number of terms: #2#
degree of polynomial in standard form: #5#

Explanation:

Determining the Standard Form of the Polynomial
Notice how your equation follows the general equation of a quintic function in standard form, #color(blue)(ax^5+bx^4+cx^3+dx^2+ex+f=0)#. Assuming that the given equation is equal to #0#, start by grouping all like terms and simplifying.

#3k^5+4k^2-6k^5-5k^2=0#

#color(green)(|bar(ul(color(white)(a/a)-3k^5-k^2=0color(white)(a/a) |)))#

Determining the Number of Terms
The number of terms of the polynomial in standard form can be found by first defining what a term is. A #color(red)("term")# is a single number, a variable, or a number and variable multiplied together.

For example (but not limited to):

  • Single numbers: #3, 56, 623, 6134, 23980#
  • Variables: #x, r, u, a, f#
  • Number and variable: #3x, 56r, 623u, 6134a, 23980f#

Going back to your equation, the terms would be the following, where the positive and negative signs are ignored after the first term:

#underbrace(-3k^5)_color(red)("term")-underbrace(k^2)_color(red)("term")=0color(white)(X),color(white)(X)#thus:

#color(green)(|bar(ul(color(white)(a/a)"number of terms"=2color(white)(a/a)|)))#

Determining the Degree
To determine the degree, take the #color(darkorange)("exponent of each variable")# of every #color(red)("term")# in the equation. The highest exponent out of all the terms is the degree of the polynomial.

#underbrace(-3k^5)_color(red)("term")-underbrace(k^2)_color(red)("term")=0#

  • #-3k^color(darkorange)5color(teal)(->)color(darkorange)5#

  • #k^color(darkorange)2color(teal)(->)color(darkorange)2#

As you can see, the highest exponent is #5#, so the degree of the polynomial is #5#. The degree of the polynomial in standard form is written mathematically as:

#color(green)(|bar(ul(color(white)(a/a)"deg"(-3k^5-k^2)=5color(white)(a/a)|)))#