Answer
$\displaystyle \frac{dy}{dx}=-4x^{-2}-2$
(rules listed in work)
Work Step by Step
SUMMARY:
The Power Rule$:\ \ \ \displaystyle \frac{d}{dx}[x^{n}]=n\cdot x^{n-1 }\ \ \ $
Sum Rule: $\displaystyle \ \ \ \frac{d}{dx}[f\pm g](x)=\frac{d}{dx}[f(x)]\pm\frac{d}{dx}[g(x)] $
Constant Multiple Rule:$\ \ \ \displaystyle \frac{d}{dx}[cf(x)]=c\cdot\frac{d}{dx}[f(x)] $
Constant times x:$\ \ \ \displaystyle \frac{d}{dx}(cx)=c\ \ \ $
Constant:$\displaystyle \ \ \ \ \ \frac{d}{dx}(c)=0 $
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$ \displaystyle \frac{dy}{dx}= \displaystyle \frac{d}{dx}[4x^{-1}-2x-10]= ...$Sum Rule$...$
$\displaystyle \frac{dy}{dx}=\frac{d}{dx}[4x^{-1}]-\frac{d}{dx}[2x]-\frac{d}{dx}[10]=$... individually:
$\displaystyle \frac{d}{dx}[4x^{-1}]$=...Constant Multiple Rule...=
$=4\displaystyle \cdot\frac{d}{dx}[x^{-1}]$=... Power Rule...
$=4(-1\cdot x^{-2})=-4x^{-2}$
$\displaystyle \frac{d}{dx}[2x]$=...Constant times x...=$2$
$\displaystyle \frac{d}{dx}[10]=$...Constant...$=0$
.
So,
$\displaystyle \frac{dy}{dx}=-4x^{-2}-2$