A) If a +b+c=6, a2 + b2 +02= 14 and a3+b3+c3=36 then prove
that abc=6.
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Answer:
(a+b+c)^2=a^2+b^2+c^2+2(ab+bc+ca)
(6)^2=14+2(ab+bc+ca)
36-14=2(ab+bc+ca)
22/2=ab+bc+ca
ab+bc+ca=11
a^3+b^3+c^3-3abc
=(a+b+c)(a^2+b^2+c^2-ab-bc-ca)
=(6)(14-11)
=(6)(3)
=18
Since, a^3+b^3+c^3-3abc=18
36-3abc=18
-3abc=18-36
-3abc=-18
abc=6
hope it helps you.....
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