a, b, c are three real numbers such that
a + b + c = 7, a2
+ b2
+ c
2
= 35 and
a
3
+ b3
+ c
3
= 151. Find the value of abc.
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Hey
Here is ur answer
We know that
(a+b+c)2= a2+ b2+c2 +2(ab+bc+ca)
(7)2=35+2(ab+bc+ca)
49-35/2= ab+bc+ca
14/2= ab+bc+ca
ab+bc+ca=7
Now
a3+b3+c3-3abc= (a+b+c)[a2+b2+c2-(ab+bc+ca)]
151-3abc=7[35-7]
151-3abc=7*28
151-3abc= 196
-3abc=45
abc= -15
Here is ur answer
We know that
(a+b+c)2= a2+ b2+c2 +2(ab+bc+ca)
(7)2=35+2(ab+bc+ca)
49-35/2= ab+bc+ca
14/2= ab+bc+ca
ab+bc+ca=7
Now
a3+b3+c3-3abc= (a+b+c)[a2+b2+c2-(ab+bc+ca)]
151-3abc=7[35-7]
151-3abc=7*28
151-3abc= 196
-3abc=45
abc= -15
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