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Re: Gp

[quote="Stuart Kovinsky"][quote="vineetbatra"]This is a GP question. Formula is a*r^(n-1), where a is the first number, r is the constant and n is the number of times constant is applied I agree that the the answer should be 62, becuase with 63 the answer will be 1008.[/quote] So...

by drian

Tue Jun 02, 2009 8:56 pm
Forum: Problem Solving
Topic: Sequence
Replies: 12
Views: 2763

sum of roots

Please help, unsure as to - 2r1r2 part of equation, Thanks [quote="ontherocks27"]For a quadratic equation ax^2+bx+c = 0 Sum of roots r1 + r2 = (-b)/a Product of roots r1r2 = c/a For the given equation r1+r2 = (- (-1))/1 = 1 r1r2 = 1/1004 Now, r1^2 +r2^2 = (r1+r2)^2 - 2r1r2 = 1 - 2(1/1004) ...

by drian

Sun May 31, 2009 8:24 pm
Forum: Problem Solving
Topic: Roots of Quadratic
Replies: 3
Views: 1247