Question 1199318
Factor: 
(2m - 3)² - (8m² - 4)²

Notice: This question on my homework has a bonus mark. I'm not sure why, and what's so special about it. Can someone help me find some extra "bonus" step at the end?

Thanks! 
<pre>This is a DOTS (Difference of Two Squares) factorization.

(2m - 3)² - (8m² - 4)²
[(2m - 3) - (8m<sup>2</sup> - 4)][(2m - 3) + (8m<sup>2</sup> - 4)] ------ Applying DOTS, or {{{matrix(1,3, a^2 - b^2, "=", (a - b)(a + b))}}}
(2m - 3 - 8m<sup>2</sup> + 4)(2m - 3 + 8m<sup>2</sup> - 4)
(- 8m<sup>2</sup> + 2m + 1)(8m<sup>2</sup> + 2m - 7)
(- 8m<sup>2</sup> + 4m - 2m + 1)(8m<sup>2</sup> + 2m - 7) ----- Factoring - 8m<sup>2</sup> + 2m + 1
(<u>- 8m<sup>2</sup> + 4m</u> - <u>2m + 1</u>)(8m<sup>2</sup> + 2m - 7)
[- 4m(2m - 1) - 1(2m - 1)](8m<sup>2</sup> + 2m - 7)
<font color = blue><font size  = 4><b>(- 4m - 1)(2m - 1)(8m<sup>2</sup> + 2m - 7)      or     - (4m + 1)(2m - 1)(8m<sup>2</sup> + 2m - 7)</font></font></b></pre>