Answer:
[tex]16x^4-72x^2+81[/tex]
Step-by-step explanation:
First, lets think of this binomial as
[tex](4x^2-9)(4x^2-9)[/tex]
To do this, we will have to use the FOIL method. This means that we multiply the First terms, Outside terms, Inside terms, and Last terms.
The first terms are both [tex]4x^2[/tex], so lets multiply these first
[tex](4x^2)^2\\\\16x^4[/tex]
Next lets multiply the outside terms, which are [tex]4x^2[/tex] and [tex]-9[/tex]
[tex](4x^2)(-9)\\\\-36x^2[/tex]
Now the inside terms, which are also [tex]4x^2[/tex] and [tex]-9[/tex]
[tex](4x^2)(-9)\\\\-36x^2[/tex]
Lastly, the last terms, which are both [tex]-9[/tex]
[tex](-9)(-9)\\\\81[/tex]
Now we have to add each of these together.
[tex]16x^4-36x^2-36x^2+81[/tex]
The last step is to combine like terms
This gives us
[tex]16x^4-72x^2+81[/tex]
