The sub-tangent at any point of the curve xm yn=am+1 varies as
(Abscissa)2
(Abscissa)3
Abscissa
Ordinate
We have, xm yn=am+1⇒m log x+n log y=(m+1)log a∴mx+nydydx=0⇒dxdy=nxmy∴Sub−tangent==∣∣ydxdy∣∣=nxm ax. Hence (c) is the correct answer.
The sub-normal at any point of the curve x2y2=a2(x2−a2) varies as