need help on this attachment
just says "which are not one to one"?
yes
or am i looking at the wrong thing? because usually you have some tougher calc problems
lol
make sure the outputs do not repeat. that is all. if they repeat it is not one to one. if they do not repeat it is one to one
f is one to one g is not because there is a 3 twice etc
at a quick glance it looks like all are one to one except g clear?
yeah, can you also help me with one more problem?
lost the site for a moment
that ok
take the derivative term by term.
\[\frac{d}{dx}\tan^{-1}(x)=\frac{1}{x^2+1}\]
so \[\frac{d}{dx}\tan^{-1}(\frac{x}{5})=\frac{1}{5}\times \frac{1}{(\frac{x}{5})^2+1}\] by the chain rule
or course you might want to clean this up a bit
\[\frac{1}{5}\frac{1}{\frac{x^2}{25}+1}\] \[\frac{5}{x^2+25}\]
damn again
\[\frac{d}{dx}\ln(x)=\frac{1}{x}\] so \[\frac{d}{dx}\ln(\sqrt{25+x^2})=\frac{1}{\sqrt{25+x^2}}\times \frac{d}{dx}\sqrt{25+x^2}\] by the chain rule again
and \[\frac{d}{dx}\sqrt{25+x^2}=\frac{1}{2\sqrt{25+x^2}}\times 2x\] again by the chain rule
so finally you get \[\frac{d}{dx}\ln(\sqrt{25+x^2})=\frac{x}{25+x^2}\]
then add them up (easy since denominators are the same) and you get \[\frac{5+x}{25+x^2}\]
Ok, so just for practice 2arc(x/3) would be 6squrt(9-x^(2)), right?
is that arcsine?
yes
you would have \[\frac{1}{\sqrt{1-(\frac{x}{3})^2}}\]
\[\frac{1}{\sqrt{1-\frac{x^2}{9}}}\]
what about the 2 on the outside
this one is a little different because of the square root.
\[\frac{1}{3}\frac{1}{\sqrt{1-\frac{x^2}{9}}}=\frac{1}{3}\frac{1}{\sqrt{\frac{9-x^2}{9}}}\]
the 9 comes outside the radical as a 3, so your "final answer" is \[\frac{1}{\sqrt{9-x^2}}\] then just multiply by 2
oh crap i made a mistake on the very first line hold on i hope i did not confuse you
\[\frac{1}{\sqrt{1-(\frac{x}{3})^2}}\] should have been \[\frac{1}{3}\frac{1}{\sqrt{1-(\frac{x}{3})^2}}\] by the chain rule. i forgot the one third out front
you have to multiply by the derivative of \[\frac{x}{3}\] which is \[\frac{1}{3}\]
oh ok
so in this case you just get \[\frac{1}{\sqrt{9-x^2}}\] when you "simplify" it. the two out front just gets multiplied at the end
ok thanks so much
yw
Join our real-time social learning platform and learn together with your friends!