Chapter 15 - Section 15.1 - Functions of Several Variables from the Numerical, Algebraic, and Graphical Viewpoints - Exercises - Page 1094: 4

$$\eqalign{ & \left( a \right)0 \cr & \left( b \right)0.4 \cr & \left( c \right)0.5 \cr & \left( d \right)0.3a - 1 \cr & \left( e \right)0.4y - 0.5x - 0.05xy \cr & \left( f \right)0.4\left( {x + h} \right) - 0.5\left( {y + k} \right) - 0.05\left( {x + h} \right)\left( {y + k} \right) \cr} $$

$$\eqalign{ & f\left( {x,y} \right) = 0.4x - 0.5y - 0.05xy \cr & \left( a \right){\text{ Find }}f\left( {0,0} \right) \cr & f\left( {0,0} \right) = 0.4\left( 0 \right) - 0.5\left( 0 \right) - 0.05\left( 0 \right)\left( 0 \right) \cr & f\left( {0,0} \right) = 0 \cr & \cr & \left( b \right){\text{ Find }}f\left( {1,0} \right) \cr & f\left( {1,0} \right) = 0.4\left( 1 \right) - 0.5\left( 0 \right) - 0.05\left( 1 \right)\left( 0 \right) \cr & f\left( {1,0} \right) = 0.4 \cr & \cr & \left( c \right){\text{ Find }}f\left( {0, - 1} \right) \cr & f\left( {0, - 1} \right) = 0.4\left( 0 \right) - 0.5\left( { - 1} \right) - 0.05\left( 0 \right)\left( { - 1} \right) \cr & f\left( {0, - 1} \right) = 0.5 \cr & \cr & \left( d \right){\text{ Find }}f\left( {a,2} \right) \cr & f\left( {a,2} \right) = 0.4a - 0.5\left( 2 \right) - 0.05a\left( 2 \right) \cr & f\left( {a,2} \right) = 0.3a - 1 \cr & \cr & \left( e \right){\text{ Find }}f\left( {y,x} \right) \cr & f\left( {y,x} \right) = 0.4y - 0.5x - 0.05xy \cr & \cr & \left( f \right){\text{ Find }}f\left( {x + h,y + k} \right) \cr & f\left( {x,y} \right) = 0.4\left( {x + h} \right) - 0.5\left( {y + k} \right) - 0.05\left( {x + h} \right)\left( {y + k} \right) \cr} $$