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​ The value of the determinant ∣b2−abb−cbc−acab−a2a−bb2−abbc−acc−aab−a2∣= ? \text { The value of the determina
Question

 The value of the determinant b2abbcbcacaba2abb2abbcaccaaba2= ? \text { The value of the determinant }\left|\begin{array}{lll}b^2-a b & b-c & b c-a c \\a b-a^2 & a-b & b^2-a b \\b c-a c & c-a & a b-a^2\end{array}\right|=\text { ? }​​

A.

abc

B.

a + b + c

C.

0

D.

ab + bc + ca

Correct option is C

​​Given determinant:Δ=b2abbcbcacaba2abb2abbcaccaaba2Factor (ba) from rows:=b(ba)bcc(ba)a(ba)abb(ba)c(ba)caa(ba)=(ba)2bbccaabbccaaApply column operation: C1C1C2=(ba)2b(bc)bcca(ab)abbc(ca)caa=(ba)2cbccbabbacaaNow, observe: C1=C3=>Two identical columns=>Determinant is zeroΔ=0\text{Given determinant:}\\[10pt]\Delta =\begin{vmatrix}b^2 - ab & b - c & bc - ac \\ab - a^2 & a - b & b^2 - ab \\bc - ac & c - a & ab - a^2\end{vmatrix}\\[12pt]\text{Factor } (b - a) \text{ from rows:}=\begin{vmatrix}b(b - a) & b - c & c(b - a) \\a(b - a) & a - b & b(b - a) \\c(b - a) & c - a & a(b - a)\end{vmatrix}\\[12pt]= (b - a)^2 \cdot\begin{vmatrix}b & b - c & c \\a & a - b & b \\c & c - a & a\end{vmatrix}\\[12pt]\text{Apply column operation: } C_1 \rightarrow C_1 - C_2\\[10pt]=(b - a)^2 \cdot\begin{vmatrix}b - (b - c) & b - c & c \\a - (a - b) & a - b & b \\c - (c - a) & c - a & a\end{vmatrix}\\[10pt]=(b - a)^2 \cdot\begin{vmatrix}c & b - c & c \\b & a - b & b \\a & c - a & a\end{vmatrix}\\[12pt]\text{Now, observe: } C_1 = C_3\\[10pt]\Rightarrow \text{Two identical columns} \Rightarrow \text{Determinant is zero}\\[12pt]\boxed{\Delta = 0}​​

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