$\text { For } f ( x , y ) = \sin ( 9 x y ) \text {, evaluate } f _ { y } \text { at the point } \left( 2 , \frac { \pi } { 4 } \right)$
A) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = \frac { 9 \pi } { 4 }$
B) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 18$
C) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 9$
D) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = \frac { 9 \pi } { 2 }$
E) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 0$

Question

$\text { For } f ( x , y ) = \sin ( 9 x y ) \text {, evaluate } f _ { y } \text { at the point } \left( 2 , \frac { \pi } { 4 } \right)$ 
A) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = \frac { 9 \pi } { 4 }$
B) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 18$
C) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 9$
D) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = \frac { 9 \pi } { 2 }$
E) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 0$

Quizplus · Accepted Answer

The Answer of $\text { For } f ( x , y ) = \sin ( 9 x y ) \text {, evaluate } f _ { y } \text { at the point } \left( 2 , \frac { \pi } { 4 } \right)$ 
A) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = \frac { 9 \pi } { 4 }$
B) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 18$
C) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 9$
D) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = \frac { 9 \pi } { 2 }$
E) $f _ { y } \left( 2 , \frac { \pi } { 4 } \right) = 0$

For f(x,y)=sin⁡(9xy), evaluate fy at the point (2,π4)\text { For } f ( x , y ) = \sin ( 9 x y ) \text {, evaluate } f _ { y } \text { at the point } \left( 2 , \frac { \pi } { 4 } \right) For f(x,y)=sin(9xy), evaluate fy​ at the point (2,4π​)

$\text { For } f ( x , y ) = \sin ( 9 x y ) \text {, evaluate } f _ { y } \text { at the point } \left( 2 , \frac { \pi } { 4 } \right)$