How do you factor completely #a^2 - 1 - 4b^2 - 4b#?
1 Answer
Dec 18, 2016
Explanation:
The difference of squares identity can be written:
#A^2-B^2 = (A-B)(A+B)#
Use this with
#a^2-1-4b^2-4b = a^2-(4b^2+4b+1)#
#color(white)(a^2-1-4b^2-4b) = a^2-(2b+1)^2#
#color(white)(a^2-1-4b^2-4b) = (a-(2b+1))(a+(2b+1))#
#color(white)(a^2-1-4b^2-4b) = (a-2b-1)(a+2b+1)#