Mister Exam

Derivative of (x+1)/(x-1)

Function f() - derivative -N order at the point
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
x + 1
-----
x - 1
x+1x1\frac{x + 1}{x - 1}
(x + 1)/(x - 1)
Detail solution
  1. Apply the quotient rule, which is:

    ddxf(x)g(x)=f(x)ddxg(x)+g(x)ddxf(x)g2(x)\frac{d}{d x} \frac{f{\left(x \right)}}{g{\left(x \right)}} = \frac{- f{\left(x \right)} \frac{d}{d x} g{\left(x \right)} + g{\left(x \right)} \frac{d}{d x} f{\left(x \right)}}{g^{2}{\left(x \right)}}

    f(x)=x+1f{\left(x \right)} = x + 1 and g(x)=x1g{\left(x \right)} = x - 1.

    To find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

    1. Differentiate x+1x + 1 term by term:

      1. The derivative of the constant 11 is zero.

      2. Apply the power rule: xx goes to 11

      The result is: 11

    To find ddxg(x)\frac{d}{d x} g{\left(x \right)}:

    1. Differentiate x1x - 1 term by term:

      1. The derivative of the constant 1-1 is zero.

      2. Apply the power rule: xx goes to 11

      The result is: 11

    Now plug in to the quotient rule:

    2(x1)2- \frac{2}{\left(x - 1\right)^{2}}


The answer is:

2(x1)2- \frac{2}{\left(x - 1\right)^{2}}

The graph
02468-8-6-4-2-1010-250250
The first derivative [src]
  1      x + 1  
----- - --------
x - 1          2
        (x - 1) 
1x1x+1(x1)2\frac{1}{x - 1} - \frac{x + 1}{\left(x - 1\right)^{2}}
The second derivative [src]
  /     1 + x \
2*|-1 + ------|
  \     -1 + x/
---------------
           2   
   (-1 + x)    
2(1+x+1x1)(x1)2\frac{2 \left(-1 + \frac{x + 1}{x - 1}\right)}{\left(x - 1\right)^{2}}
The third derivative [src]
  /    1 + x \
6*|1 - ------|
  \    -1 + x/
--------------
          3   
  (-1 + x)    
6(1x+1x1)(x1)3\frac{6 \left(1 - \frac{x + 1}{x - 1}\right)}{\left(x - 1\right)^{3}}
The graph
Derivative of (x+1)/(x-1)