Question 334833
<pre><b>
Learn the rule for factoring the difference of two squares

Rule:  {{{red(A)^2-green(B)^2=(red(A)+green(B))(red(A)-green(B))}}}

{{{t^4 - 1}}}

Write that as 

{{{(red(t^2))^2-green(1)^2}}}

Apply the rule above:

{{{(red(t^2)+green(1))(red(t^2)-green(1))}}}

Write what's in the second parentheses this way:

{{{(t^2+1)(red(t)^2-green(1)^2)}}}

Apply the rule to the second parentheses:

{{{(t^2+1)(red(t)+green(1))(red(t)-green(1))}}}

(Notice that the rule does not work for the sum of two squares,
so we have to leave the first parentheses just as it is because
of the + between the terms.)

Edwin</pre>