25-08-09 Cubic equation...

If a, b, c are the roots of x3+2x2+3x+3 then

\left( \frac{a}{a+1}\right)^3+\left( \frac{b}{b+1}\right)^3+\left( \frac{c}{c+1}\right)^3 is equal to

(Another good one i got from a student)

10 Answers

11
Mani Pal Singh ·

thoda lamba aa ra hai[2]

a+b+c=-2
ab+bc+ca=3
abc=-3

solve further!!!!!!!!!

I just got this method in the bag
but will be pleased to see more[1]

11
Devil ·

Now using the relations a3+b3+c3=(a+b+c)3-3(a+b)(b+c)(c+a), we can evaluate the entire expression....

If full solution is needed, do nudge me!

But I think this is sufficient, isn't it Nishant Sir?

62
Lokesh Verma ·

There is a far far simpler way to think!

11
Mani Pal Singh ·

ya
by symmetry we observe that [12][12][12]
what do we observe[3]

1
archana anand ·

wats da answer???

1
Bicchuram Aveek ·

NISHANT SIR DER ????

49
Subhomoy Bakshi ·

answer is 12

106
Asish Mahapatra ·

44 .. unless there is sum calc. mistake

49
Subhomoy Bakshi ·

using, a3+b3+c3-3abc=(a+b+c)(ab+bc+ca)

1
Philip Calvert ·

[7]

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