If The Lines ax + y + 1 = 0, x + by + 1 = 0 And x + y + c = 0 (a, b and cbeing Distinct And Difference From 1) Are Concurrent, Then Find The Value Of. 

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Question

If the lines ax + y + 1 = 0, x + by + 1 = 0 and x + y + c = 0 (ab and cbeing distinct and difference from 1) are concurrent, then find the value of

Solution

Correct option is

1

 

The given lines are concurrent, then  

       

                                    (applying C2 → C2 – C1 and C→ C3 – C1)

Expanding along first row  

  

  

Dividing by (1 – a)(1 – b)(1 – c) then  

       

    

Hence, 

       .

SIMILAR QUESTIONS

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Q4

 

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Q5

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Q6

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Q7

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Q8

 

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Q9

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Q10

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