Let F(x, Y) = X $y ^ { 2 }$ $x ^ { 2 }$

Short Answer

Let f(x, y) = x $y ^ { 2 }$ + $x ^ { 2 }$ . Simplify $\frac { f ( x + h , y ) - f ( x , y ) } { h }$ for h ≠ 0.
Enter your answer exactly in the form: $a x + y ^ { n } + b$