Question

Which of the equations are true identities?

Answer 1

only a

Explanation:

Answer 2

`m^(3)-1=(m-1)(1+m+m^(2) ) \\m^(3)-1=m+m^(2)+m^(3) -1-m-m^(2)\\ m^(3)-1=m^(3)-1`

`(n+3)^(2)+2n=8n+13\\n^(2)+6n+9+2n=8n+13\\ n^(2)+8n+9=8n+13`

answer: only A