- #1
Kenji Liew
- 25
- 0
Homework Statement
\begin{equation}
f(x)=
\begin{cases}
5x+2 &, x \leq 1 \\
3x^2 &, 1<x<2\\
4-x &, x\geq 2
\end{cases}
\end{equation}
\begin{equation}
g(x)=
\begin{cases}
\frac{1}{5}(2+3 cos x) &, x <0 \\
4-sin x &, x \geq 0
\end{cases}
\end{equation}
Find [itex] h = f \circ g [/itex] and then by using chain rule to find the derivative of [itex] f \circ g [/itex] .
Homework Equations
\begin{equation}
h(x)=f\circ g =
\begin{cases}
4+3 cos x &, x <0 \\
sin x &, x \geq 0
\end{cases}
\end{equation}
The Attempt at a Solution
From [itex] h(x) = f \circ g [/itex] above, I directly differentiate and I get the following
\begin{equation}
h'(x)=
\begin{cases}
-3 sin x &, x < 0 \\
cos x &, x > 0
\end{cases}
\end{equation}
If chain rule are requested in finding the derivative, I know the formula is [itex] h'(x) = f' (g(x)) \cdot g'(x) [/itex]. Any idea to find the derivative using chain rule?
Thank you.