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anonymous
 4 years ago
2x4+4x6+6x8.........to n terms..... how to get the 20th term of this sequence
anonymous
 4 years ago
2x4+4x6+6x8.........to n terms..... how to get the 20th term of this sequence

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Un=4n^2+4n U20=4(20)^2+4(20) =1680

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0how to reach that equation??

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.18 24 48 ... 16 24 8 maybe, then we take the first diagonal and apply some pascal to it with any luck

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0When we do sequences(or series) we always need to take the term number into our thinking process. So, naturally, we look at the first term and say 2 times one is 2 so 2n is part of the equation somehow.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0sry, i have a way of doing it, but its not that easy to explain...once you do lots of series and sequences, there tends to be a patter like usually n+1 or n+2 or 2n is involved. Just checks work with my method.

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.18*nC0+16*nC1+8*nC2 this is similar to what i recall; prolly needs to be refreshed to be accurate tho

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.18*1+16n+8n(n1)/2 lets see if this is a good recollection lol 8 + 16n +4n^24n 4n^2 12n +8 ?

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1when n=0, we get 8 when n=1 we get 0 ... doh!!

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.12,4,6 = 2+2(n1) x 4,6,8 = 4+2(n1) an = (2+2n2) * (4+2n2) a20 = (2+2(20)2)*(4+2(20)2) = (2(20))*(2+2(20)) = (40)*(42) = 1680 ?? yay, we match now
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