Problem $3.$

$(1$ point$)$ Let $f(x,y)=sin(3x+8y)$ and $P=(\frac{}{3},\frac{1}{4}).$ Find the maximum rate of change of the fucntion $f$ at the point $P.$

A$.-\sqrt[\phantom{2}]{73}$

B$.($:$-3,-8$:$)$

c$.\sqrt[\phantom{2}]{73}($:$-1,-1$:$)$

D$.\sqrt[\phantom{2}]{73}$

E