if a+b+c=5 and ab+bc+ac=10, then find a^3+b^3+c^3-3abc= -25
Muthu2004:
What should I find
you need to prove that a cube plus b cube plus c cube minus 3abc equals to minus 25
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(a+b+c)^2 =a^2+b^2+c^2+2(ab+bc+ca)
(5)^2=a^2+b^2+c^2+2*10
25-20=5=a^2+b^2+c^2
a^3+b^3+c^3-3abc
=(a+b+c) (a^2+b^2+c^2-(ab+bc+ca))
=5(5-10)
=5*-5= -25
Hence proved.
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(5)^2=a^2+b^2+c^2+2*10
25-20=5=a^2+b^2+c^2
a^3+b^3+c^3-3abc
=(a+b+c) (a^2+b^2+c^2-(ab+bc+ca))
=5(5-10)
=5*-5= -25
Hence proved.
I hope it will help you.
Please mark it as brainliest
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