Problem of the Week

Updated at Dec 11, 2017 11:28 AM

This week we have another calculus problem:

How would you differentiate secx+cscx\sec{x}+\csc{x}?

Let's start!



ddxsecx+cscx\frac{d}{dx} \sec{x}+\csc{x}

1
Use Sum Rule: ddxf(x)+g(x)=(ddxf(x))+(ddxg(x))\frac{d}{dx} f(x)+g(x)=(\frac{d}{dx} f(x))+(\frac{d}{dx} g(x)).
(ddxsecx)+(ddxcscx)(\frac{d}{dx} \sec{x})+(\frac{d}{dx} \csc{x})

2
Use Trigonometric Differentiation: the derivative of secx\sec{x} is secxtanx\sec{x}\tan{x}.
secxtanx+(ddxcscx)\sec{x}\tan{x}+(\frac{d}{dx} \csc{x})

3
Use Trigonometric Differentiation: the derivative of cscx\csc{x} is cscxcotx-\csc{x}\cot{x}.
secxtanxcscxcotx\sec{x}\tan{x}-\csc{x}\cot{x}

Done