Find the derivative. $(2$ marks $)$ y $=(1/2)$x$10-(1/5)$x$5($dy$/$dx$)=5$x$11-$ x$6($dy$/$dx$)=5$x$10-$ x$5($dy$/$dx$)=5$x$9-$ x$4($dy$/$dx$)=(1/2)$x$9-(1/5)$x$4$