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Linearazationish Problem

  • #1
784
11

Homework Statement


If z=x^2-xy+3y^2 and (x,y) changes from (3,-1) to (2.96,-.95) compare the values of Δz and dz.



The Attempt at a Solution


So I plugged the two given sets of (x,y) into and solved for z and subtracted one from the other and got |.7189|. I don't know what the question means when it says compare it to dz. Since z is a function of two variables how do I do this? To I take the partial with regards to each variable or whaaat? does anyone know what the question is asking?
 

Answers and Replies

  • #3
784
11
so I took the function partial of x and added it to the partial of y. it wants me to compare delta_z with dz. Which numbers should I plug in for dz? The initial values or final?
 
  • #4
UltrafastPED
Science Advisor
Gold Member
1,912
216
Try the difference of both!
 
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