A. tan-1(6/13)

B. tan-1(3/4)

C. tan-1(5/√3)

D. tan-1(4√2/7)

If the normal to the curve x^{3}-y^{2} =0 at (m^{2}, -m^{3}) is y=mx-2m^{3}, then the value of m^{2 }is

The curves y=x^{2}-1, y=8x-x^{2}-9 touch each other at the point (2, 3). The equation of the common normal is

If the subnormal of the curve xy^{n}=a^{n+1} is constant, then the value of n is

The equation of tangent to the curve y=x+9/x+5 so that is passes through the origin is

If θ is the angle between the curves y=sin x, y =cosx at x=π/4 then tan θ=