Reflection of the line $x+y+1=0$ in the line $l x+m y+n=0$ is

$(x+y+1)(l+m)-2\left(l^2+m^2\right)(l x+m y+n)=0$

$(l+m+1)(x+y)-2(l x+m y)\left(l^2+m^2\right)=0$

JEE MATHEMATICS MCQ: PAIR OF STRAIGHT LINES

1 Easy

1 of 1

Application +4 | -1

Reflection of the line

x+y+1=0

in the line

l x+m y+n=0

View answer and explanation

Correct option: B

(x+y+1)\left(l^2+m^2\right)-2(l+m)(l x+m y+n)=0

Option B (

(x+y+1)(l^2+m^2)-2(l+m)(l x+m y+n)=0

) is correct because it represents the reflection of the line x+y+1=0 in the line lx+my+n=0.

Practice All Chapter MCQs →

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