- #1
misogynisticfeminist
- 370
- 0
If [tex]\sum^{n}_{r=1} u_r =3n^2 +4n [/tex], what is [tex] \sum^{n-1}_{r=1}u_r [/tex] ?
I know that [tex] \sum^{n-1}_{r=1}u_r [/tex] is equals to [tex]\sum^{n}_{r=1} u_r =3n^2 +4n - u_n [/tex] but the answer given is [tex] 3n^2-2n-1[/tex]. How do i express it in that way?
thanks alot.
I know that [tex] \sum^{n-1}_{r=1}u_r [/tex] is equals to [tex]\sum^{n}_{r=1} u_r =3n^2 +4n - u_n [/tex] but the answer given is [tex] 3n^2-2n-1[/tex]. How do i express it in that way?
thanks alot.