Answer:
(9m-1)(9m+1)
Step-by-step explanation:
This is a difference of squares
(9m)^2-1^2
Use a^2-b^2=(a-b)(a+b)
So the answer is (9m-1)(9m+1)
Answer:
Step-by-step explanation:
[tex]81m^2-1=9^2m^2-1^2=(9m)^2-1^2\\\\\text{use}\ a^2-b^2=(a-b)(a+b)\\\\=(9m-1)(9m+1)[/tex]