Find dydx when x and y are connected by the relation given.
sin (xy)+xy=x2−y
We have, sin(xy)+xy=x2−y
On differentiating both sides. w.r.t. x, we get
ddx(sin xy)+ddx(xy)=ddx(x2)−dydx⇒cos (xy).ddx(xy)+yddxx−x.ddxyy2=2x−dydx⇒cos (xy).[x.dydx+y]+y−xdydxy2=2x−dydx⇒x cos (xy).dydx+y cos (xy)+yy2−xy2dydx=2x−dydx⇒dydx[x cos (xy)−xy2+1]=2x−y cos (xy)−yy2∴ dydx=[2xy−y2coxy−1y][y2xy2cosxy−x+y2]=(2xy−y2cos (xy)−1)(xy2cos (xy)−x+y2)