1. Given z=x²+3xy-2y² Estimate the change in z when x changes from 2 to 2,5 and y changes from 3 to 2,52. I am stuck with the math and can't figure it out as what I need to do further.3.
a=2
b=3
Δx= +0,5
Δy= -0,5
dz/dx = 2x+3y
=2(2)+3(3)
=13
dz/dy = 3x-4y
=...