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JEE Main20248 Apr 2024Evening ShiftMathematicsStraight LinesActual

Let a ray of light passing through the point (3,10) reflects on the line 2 x+y=6 and the reflected ray passes through the point (7,2) . If the equation of the incident ray is a x+b y+1=0 , then a^2+b^2+3 a b is equal to_________

Correct answer

0

Step-by-step solution

For B^ x-7 2 = y-2 1 =-2 ( 14+2-6 5 ) aligned & x-7 2 = y-2 1 =-4 & x=-1 y=-2 B^ (-1,-2) aligned incident ray AB ^ aligned & M_ AB ^ =3 & y+2=3(x+1) & 3 x-y+1=0 & a=3 b=-1 & a^2+b^2+3 a b=9+1-9=1 aligned

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