SOLUTION: i need help please can anyone tell me what is the next number in the series of following numbers 701495 , 841853 , 676836

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Question 944299: i need help please can anyone tell me what is the next number in the series of following numbers 701495 , 841853 , 676836
please its urgent
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Assume a quadratic general formula:

a%5Bn%5D=An%5E2%2Bbn%2Bc, a%5B1%5D=701495, a%5B2%5D=841853, a%5B3%5D=676836

Substitute n=1

a%5B1%5D=A%281%29%5E2%2BB%281%29%2BC

701495=A%2BB%2BC

Substitute n=2

a%5B2%5D=A%282%29%5E2%2BB%282%29%2BC

841853=4A%2B2B%2BC

Substitute n=3

a%5B3%5D=A%283%29%5E2%2BB%283%29%2BC

676836=9A%2B3B%2BC

Now we have this system of equations to solve:

system%28A%2BB%2BC=701495%2C4A%2B2B%2BC=841853%2C9A%2B3B%2BC=676836%29

Solve that and get A = -152687.75, B=598420.5, C=255762

So the formula is a%5Bn%5D=-152687.75n%5E2%2B598420.5n%2B255762

Substituting n=4 gives

a%5B4%5D=-152687.75%284%29%5E2%2B598420.5%284%29%2B255762

a%5B4%5D=206444

Edwin