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#1 2008-02-15 17:10:05
- Melllyy
- Guest
Last algebra question :)
Multiply 3 consecutive numbers together and then add the middle number
eg (1 x 2 x 3) + 2 = 8
So i figured the answer is the middle number cubed
Prove your answer using algebra (hint make the middle number n)
#2 2008-02-15 18:38:38
- John E. Franklin
- Member
- Registered: 2005-08-29
- Posts: 3,588
Re: Last algebra question :)
small is n-1
big is n+1
middle is n
small * big = n^2 - 1
that * middle = n^3 - n
that + middle = n^3
Hurray!!
igloo myrtilles fourmis
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