मराठी

Show that Δ = pqpqqqppq|xpqpxqqqx|=(x-p)(x2+px-2q2) - Mathematics

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प्रश्न

Show that Δ = `|(x, "p", "q"),("p", x, "q"),("q", "q", x)| = (x - "p")(x^2 + "p"x - 2"q"^2)` 

बेरीज
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उत्तर

Applying C1 → C1 – C2, we have

Δ = `|(x - "p", "p", "q"),("p" - x, x, "q"),(0, "q", x)|`

= `(x - "p")|(1, "p", "q"),(-1, x, "q"),(0, "q", x)|`

= `(x - "p")|(0, "p" + x, 2"p"),(-1, x, "q"),(0, "q", x)|`  Applying R1 → R1 – R2 

Expanding along C1, we have

Δ = `(x - "p")("p"x + x^2 - 2"q"^2)`

= `(x - "p")(x^2 + "p"x - 2"q"^2)` 

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पाठ 4: Determinants - Solved Examples [पृष्ठ ७०]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 4 Determinants
Solved Examples | Q 4 | पृष्ठ ७०

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