Ask your own question, for FREE!
Mathematics 11 Online
OpenStudy (anonymous):

Implicit differentiation to find the slope of the tangent line

OpenStudy (anonymous):

OpenStudy (anonymous):

\[\frac{ y }{ x-3y }=x^9-2\] differentiate w.r.t. x \[\frac{ \left( x-3y \right)\frac{ dy }{ dx }-y \left( 1-3 \frac{ dy }{ dx } \right) }{ \left( x-3y \right) ^2}=9x^8\] \[\left( x-3y+3y \right)\frac{ dy }{ dx }-y=9x^2\left( x-3y \right)^2\] \[\frac{ dy }{ dx }=9x \left( x-3y \right)^2\] put x=1,\[y=\frac{ -1 }{ -2 }=\frac{ 1 }{ 2 },we~get\] ?

OpenStudy (anonymous):

so do i plug in the x and y into the 9x(x-3y)^2 ?

OpenStudy (anonymous):

it gave me 2.25

OpenStudy (anonymous):

correction it is\[9 x^7(x-3y)^2\] i wrote by mistake 9x^2,it should be 9x^8

OpenStudy (anonymous):

in place of 9x write 9x^7

OpenStudy (anonymous):

it would still give the same answer since x is 1 isn't it?

OpenStudy (anonymous):

but the answer remains the same.

OpenStudy (anonymous):

it says the answer is incorrect?

OpenStudy (anonymous):

i feel like im doing something wrong but im not sure

OpenStudy (anonymous):

you can use the quotient rule, or you can multiply out first

OpenStudy (anonymous):

might be easier to do with with \[y=(x^9-2)(x-3y)\] i.e. \[y=x^{10}-3 x^9 y-2 x+6 y\]

OpenStudy (anonymous):

then do i find the derivative of that?

OpenStudy (anonymous):

wait that confuses me

OpenStudy (freckles):

yes differentiate that

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!