If The Line ax + by + c = 0 Is A Normal To The Curve xy = 1 Then

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If the line ax + by + c = 0 is a normal to the curve xy = 1 then


Correct option is

a > 0, b < 0 & a < 0, > 0

ax + by + c = 0

Normal to xy = 1   






So sign of a and sign of b are opposite.


You could have also argued that us 


⇒ Decreasing function  

  Slope < 0 always ⇒ Slope of Normal > 0 always  

⇒ Sign of a and b must be opposite. 



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