The following 3d plot and contour plot might help:
Note also that the gradient in the x-direction is 2x - 4 and in the y-direction is 2y + 2, and that these gradients must be zero at the minimum.
Find the values of x and y from 2x - 4 = 0 and 2y + 2 = 0, then put these values back into your expression for temperature.
.
The following 3d plot and contour plot might help:
Note also that the gradient in the x-direction is 2x - 4 and in the y-direction is 2y + 2, and that these gradients must be zero at the minimum.
Find the values of x and y from 2x - 4 = 0 and 2y + 2 = 0, then put these values back into your expression for temperature.
.