Can anyone help me find me error on my work? (Derivatives)
I'll be writing out step by step so that it is easier to find out.
\[y=\frac{ -3x^3+3x }{ \sqrt{2-x^2} }\]
\[y'=\frac{ (-9x^2+3)(\sqrt{2-x^2}-(-3x^3+3x)(\frac{ 1 }{ 2 })(2-x^2)^\frac{ -1 }{ 2 }(-2x) }{ (\sqrt{2-x^2)^2} }\]
the power of 2 is outside the square root. My mistake.
correct :)
ok from now on I will simplify the numerator part only, so I will use the denominator later.
\[y'= -9x^2\sqrt{2-x^2}+3\sqrt{2-x^2}-\frac{ (-3x^3+3x)(-2x)}{ 2\sqrt{2-x^2} }(-3x^3+3x)(-2x)\]
delete the part after the fraction. That wasn't suppose to be there.
correct:)
\[y'=-9x^2\sqrt{2-x^2}+3x \sqrt{2-x^2}-\frac{ 3x^4+3x^2 }{ \sqrt{2-x^2} }\]
I'm starting to simplify it as much as I can by finding common denominators and so on.
\[y'= -9x^2\sqrt{2-x^2}+\frac{ 3(2-x) }{ \sqrt{2-x^2} }- \frac{ 3x^4+3x^2 }{ \sqrt{2-x^2} }\]
\[y'= -9x^2\sqrt{2-x^2}+\frac{ 6-3x^2-3x^4-3x^2 }{ \sqrt{2-x^2} }\]
\[y'= -9x^2\sqrt{2-x^2} + \frac{ -3x^4 -6x^2 +6 }{ \sqrt{2-x^2} }\]
wait
\[y'= \frac{ -9x^(2-x^2) }{ \sqrt{2-x^2} }-\frac{ 3x^4+6x^2-6 }{ \sqrt{2-x^2} }\]
what's the equation after i said correct
Derivative without using the denominator.
wait
I think I just found out where is the problem
\[-\frac{(-3x^4 -3x^2) }{ \sqrt{2-x^2} }\]
|dw:1405587154576:dw| this is the answer i solved it in my book
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