Derivative of Composite Function/Examples/Root of Arcsine of x

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Example of Derivative of Composite Function

$\map {\dfrac \d {\d x} } {\sqrt {\arcsin x} } = \dfrac 1 {2 \sqrt {\paren {1 - x^2} \arcsin x } }$


Proof

Let $u = \arcsin x$.

Let $y = u^{1/2}$.

Thus we have:

$y = \paren {\arcsin x}^{1/2}$

and so:

\(\ds \dfrac {\d y} {\d x}\) \(=\) \(\ds \dfrac {\d y} {\d u} \dfrac {\d u} {\d x}\) Derivative of Composite Function
\(\ds \) \(=\) \(\ds \dfrac 1 {2 \sqrt u} \cdot \dfrac 1 {\sqrt {1 - x^2} }\) Power Rule for Derivatives, Derivative of Arcsine Function
\(\ds \) \(=\) \(\ds \dfrac 1 {2 \sqrt {\paren {1 - x^2} \arcsin x } }\) simplification

$\blacksquare$


Sources