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​If (a+b+c)=12, and (a2+b2+c2)=50, find the value of (a3+b3+c3−3abc).\text{If } (a + b + c) = 12, \text{ and }
Question

If (a+b+c)=12, and (a2+b2+c2)=50, find the value of (a3+b3+c33abc).\text{If } (a + b + c) = 12, \text{ and } (a^2 + b^2 + c^2) = 50, \text{ find the value of } (a^3 + b^3 + c^3 - 3abc).​​

A.

36

B.

24

C.

42

D.

48

Correct option is A

Given:

If(a+b+c)=12,and(a2+b2+c2)=50If (a + b + c) = 12, and (a^2 + b^2 + c^2) = 50​​

Formula Used:

(a+b+c)2=a2+b2+c2+2(ab+bc+ca)(a + b + c)^2 = a^2 + b^2 + c^2 + 2(ab + bc + ca)​​

(a3+b3+c33abc)=(a+b+c)((a2+b2+c2)(ab+bc+ca))(a^3 + b^3 + c^3 - 3abc) = (a + b + c)((a^2 + b^2 + c^2) - (ab + bc + ca))​​

Solution:

(a+b+c)2=a2+b2+c2+2(ab+bc+ca)(a + b + c)^2 = a^2 + b^2 + c^2 + 2(ab + bc + ca)​​

122=50+2(ab+bc+ca)12^2 = 50 + 2(ab + bc + ca)​​

144 = 50 + 2(ab + bc + ca)

2(ab + bc + ca) = 144 - 50 = 94

ab + bc + ca = 94/2 = 47

(a3+b3+c33abc)=(a+b+c)((a2+b2+c2)(ab+bc+ca))(a^3 + b^3 + c^3 - 3abc) = (a + b + c)((a^2 + b^2 + c^2) - (ab + bc + ca))​​

Substituting the known values:

(a3+b3+c33abc)=12(5047) (a3+b3+c33abc)=12×3=36(a^3 + b^3 + c^3 - 3abc) = 12(50 - 47)\\\ \\(a^3 + b^3 + c^3 - 3abc) = 12 × 3 = 36​​

Thus, the value of (a3+b3+c33abc)(a^3 + b^3 + c^3 - 3abc) ​is 36.

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