Question

Se poate aplica vreo formula pentru a separa cei doi termeni ai numitorului in cazul urmator: 1/(2k-1)(2k+1)?

Answer 1

1/[tex]\frac{1}{(2k-1)(2k+1)}=\frac{1}{2}\frac{2}{(2k-1)(2k+1)}=\frac{1}{2}\frac{2k+1-(2k-1)}{(2k-1)(2k+1)}=\\ \frac{1}{2}[\frac{2k+1}{(2k-1)(2k+1)}-\frac{2k-1}{(2k-1)(2k+1)}]=\frac{1}{2}[\frac{1}{2k-1}-\frac{1}{2k+1}][/tex]