How do you factor by grouping #2n^2 + 5n + 2#?

1 Answer
May 17, 2015

#2n^2 + 5n + 2#

#= 2n^2 + 4n + n + 2#

#= 2n(n+2)+1(n+2)#

#= (2n+1)(n+2)#

The 'trick' is the particular separation of #5n# into #4n+n#, which results in the ratio of the first to second coefficients being the same as the ratio of the third to fourth coefficients.