If the line ax+by+c=0 is a normal to the curve xy=1, then:(A)a>0,b>0(B)a>0,b<0(C)a<0,b<0(D)data is insufficient.

Dear Jayati

ax+by+c=0

slope of line m1 =-a/b

now for curve

xy=1

differentiate

xdy/dx +y=0

dy/dx =-y/x

 dy/dx =-1/x²

this is the slope of tangent

then slope of normal at any point is m =x²

so -a/b =x²

a and b should be apposite sign

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