i dont understand neither why do you choose one or other function, to set equal to zero, if you did it on the second one, why you didnt do it on the first one?
In order for -4y(1+y^2) to be 0 either -4y has to be 0 or 1+y^2 has to be 0, but if 1+y^2 was 0 then y^2 would have to be -1, and there is no real number that is equal to -1 when squared. This means -4y must be 0, that is, y=0. Both f_x and f_y were set equal to 0. In f_x, 2x was factored out, and f_y was divided by 2.
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I think between 7.25 and 8. you did a mistake when x = 0, f(x,y) should be y^2
Oops, I reversed the results on the two axes. Good catch!
@@asherroberts TRUMP 2024
Thank you for correcting it! I was lost when I saw that, because I was learning it as a whole brand new stuff right now.
in example 4 i think you skip a lot of things and u just do it without explain from where the things come and that confuse me a little to be honest
i dont understand the part that you say "y" Is zero, because it cannot be nagative one, and im like lost from there
i dont understand neither why do you choose one or other function, to set equal to zero, if you did it on the second one, why you didnt do it on the first one?
In order for -4y(1+y^2) to be 0 either -4y has to be 0 or 1+y^2 has to be 0, but if 1+y^2 was 0 then y^2 would have to be -1, and there is no real number that is equal to -1 when squared. This means -4y must be 0, that is, y=0.
Both f_x and f_y were set equal to 0. In f_x, 2x was factored out, and f_y was divided by 2.
Thank you very much!