A difficulty in understanding 2 examples in Petrovic. Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?A difficulty in understanding the solution of Exam GRE 0568 Q31.A difficulty in understanding a use of Cauchy Schwartz inequality.Difficulty(3) in understanding the completeness of $l_2.$A difficulty in understanding theorem 4.2 in Israel Gohberg.A difficulty in understanding Theorem 4.3 in Israel Gohberg.A difficulty in understanding a proof for L'Hospital's rule (in Petrovic)A difficulty in understanding the proof of 7.2.3 Petrovic.A difficulty in understanding a statement in example 10.6.6 Petrovic.A difficulty in understanding a step in the proof of Thm. 11.5.6 in Petrovic.A difficulty in understanding multivariable Fermat theorem proof.
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A difficulty in understanding 2 examples in Petrovic.
Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)
Announcing the arrival of Valued Associate #679: Cesar Manara
Unicorn Meta Zoo #1: Why another podcast?A difficulty in understanding the solution of Exam GRE 0568 Q31.A difficulty in understanding a use of Cauchy Schwartz inequality.Difficulty(3) in understanding the completeness of $l_2.$A difficulty in understanding theorem 4.2 in Israel Gohberg.A difficulty in understanding Theorem 4.3 in Israel Gohberg.A difficulty in understanding a proof for L'Hospital's rule (in Petrovic)A difficulty in understanding the proof of 7.2.3 Petrovic.A difficulty in understanding a statement in example 10.6.6 Petrovic.A difficulty in understanding a step in the proof of Thm. 11.5.6 in Petrovic.A difficulty in understanding multivariable Fermat theorem proof.
$begingroup$
Those are the two examples:

But it is not clear for me how example 1 shows if $f$ is injective then $Df$ is injective, could anyone explain for me how this is shown please?
Also in example 2:
1-It is not clear for me why he wrote in DF(a) an $x$, what is this $x$ multiplied by the given matrix, from where it comes?
2-Also I do not understand how he proved that the injectivity of the derivatives implies the injectivity of $**f**$? more precisely I do not understand why $DF(a)(x_1) = DF(a)(x_2)$ iff $x_1 = x_2$ and also what is the importance of saying $**f**(t_1) = **f**(t_2)$ implies $t_1 = t_2$, is there a relation between $t_1$ and $x_1$, and $t_2$ and $x_2$ ?
3-It is not clear for me also why the inverse is incorrect i.e. injectivity of $f$ does not imply injectivity of the derivative, could anyone clarify this for me please?
Could anyone clarify this points for me please?
real-analysis calculus analysis multivariable-calculus implicit-function-theorem
$endgroup$
add a comment |
$begingroup$
Those are the two examples:

But it is not clear for me how example 1 shows if $f$ is injective then $Df$ is injective, could anyone explain for me how this is shown please?
Also in example 2:
1-It is not clear for me why he wrote in DF(a) an $x$, what is this $x$ multiplied by the given matrix, from where it comes?
2-Also I do not understand how he proved that the injectivity of the derivatives implies the injectivity of $**f**$? more precisely I do not understand why $DF(a)(x_1) = DF(a)(x_2)$ iff $x_1 = x_2$ and also what is the importance of saying $**f**(t_1) = **f**(t_2)$ implies $t_1 = t_2$, is there a relation between $t_1$ and $x_1$, and $t_2$ and $x_2$ ?
3-It is not clear for me also why the inverse is incorrect i.e. injectivity of $f$ does not imply injectivity of the derivative, could anyone clarify this for me please?
Could anyone clarify this points for me please?
real-analysis calculus analysis multivariable-calculus implicit-function-theorem
$endgroup$
add a comment |
$begingroup$
Those are the two examples:

But it is not clear for me how example 1 shows if $f$ is injective then $Df$ is injective, could anyone explain for me how this is shown please?
Also in example 2:
1-It is not clear for me why he wrote in DF(a) an $x$, what is this $x$ multiplied by the given matrix, from where it comes?
2-Also I do not understand how he proved that the injectivity of the derivatives implies the injectivity of $**f**$? more precisely I do not understand why $DF(a)(x_1) = DF(a)(x_2)$ iff $x_1 = x_2$ and also what is the importance of saying $**f**(t_1) = **f**(t_2)$ implies $t_1 = t_2$, is there a relation between $t_1$ and $x_1$, and $t_2$ and $x_2$ ?
3-It is not clear for me also why the inverse is incorrect i.e. injectivity of $f$ does not imply injectivity of the derivative, could anyone clarify this for me please?
Could anyone clarify this points for me please?
real-analysis calculus analysis multivariable-calculus implicit-function-theorem
$endgroup$
Those are the two examples:

But it is not clear for me how example 1 shows if $f$ is injective then $Df$ is injective, could anyone explain for me how this is shown please?
Also in example 2:
1-It is not clear for me why he wrote in DF(a) an $x$, what is this $x$ multiplied by the given matrix, from where it comes?
2-Also I do not understand how he proved that the injectivity of the derivatives implies the injectivity of $**f**$? more precisely I do not understand why $DF(a)(x_1) = DF(a)(x_2)$ iff $x_1 = x_2$ and also what is the importance of saying $**f**(t_1) = **f**(t_2)$ implies $t_1 = t_2$, is there a relation between $t_1$ and $x_1$, and $t_2$ and $x_2$ ?
3-It is not clear for me also why the inverse is incorrect i.e. injectivity of $f$ does not imply injectivity of the derivative, could anyone clarify this for me please?
Could anyone clarify this points for me please?
real-analysis calculus analysis multivariable-calculus implicit-function-theorem
real-analysis calculus analysis multivariable-calculus implicit-function-theorem
edited Apr 1 at 1:20
hopefully
asked Mar 31 at 22:48
hopefullyhopefully
190215
190215
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