Let a – 2b + c = 1.
If $$f(x)=\left| {\matrix{
{x + a} & {x + 2} & {x + 1} \cr
{x + b} & {x + 3} & {x + 2} \cr
{x + c} & {x + 4} & {x + 3} \cr
} } \right|$$, then:
Solution
R<sub>1</sub> $\to$ R<sub>1</sub> + R<sub>3</sub> – 2R<sub>2</sub>
<br><br>f(x) = $$\left| {\matrix{
{a + c - 2b} & 0 & 0 \cr
{x + b} & {x + 3} & {x + 2} \cr
{x + c} & {x + 4} & {x + 3} \cr
} } \right|$$
<br><br>= (a + c – 2b) ((x + 3)<sup>2</sup> – (x + 2)(x + 4))
<br><br>= x<sup>2</sup> + 6x + 9 – x<sup>2</sup> – 6x – 8 = 1
<br><br>$\therefore$ f(x) = 1
<br><br>$\Rightarrow$ f(50) = 1
About this question
Subject: Mathematics · Chapter: Sets, Relations and Functions · Topic: Sets and Operations
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