Mister Exam

Derivative of -(x+1)/(4x+7)

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
 -1 - x
-------
4*x + 7
x14x+7\frac{- x - 1}{4 x + 7}
d / -1 - x\
--|-------|
dx\4*x + 7/
ddxx14x+7\frac{d}{d x} \frac{- x - 1}{4 x + 7}
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)=x1f{\left(x \right)} = - x - 1 and g(x)=4x+7g{\left(x \right)} = 4 x + 7.

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

    1. Differentiate x1- x - 1 term by term:

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

      2. The derivative of a constant times a function is the constant times the derivative of the function.

        1. Apply the power rule: xx goes to 11

        So, the result is: 1-1

      The result is: 1-1

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

    1. Differentiate 4x+74 x + 7 term by term:

      1. The derivative of the constant 77 is zero.

      2. The derivative of a constant times a function is the constant times the derivative of the function.

        1. Apply the power rule: xx goes to 11

        So, the result is: 44

      The result is: 44

    Now plug in to the quotient rule:

    3(4x+7)2- \frac{3}{\left(4 x + 7\right)^{2}}


The answer is:

3(4x+7)2- \frac{3}{\left(4 x + 7\right)^{2}}

The graph
02468-8-6-4-2-1010-200200
The first derivative [src]
     1      4*(-1 - x)
- ------- - ----------
  4*x + 7            2
            (4*x + 7) 
4(x1)(4x+7)214x+7- \frac{4 \left(- x - 1\right)}{\left(4 x + 7\right)^{2}} - \frac{1}{4 x + 7}
The second derivative [src]
  /    4*(1 + x)\
8*|1 - ---------|
  \     7 + 4*x /
-----------------
             2   
    (7 + 4*x)    
8(4(x+1)4x+7+1)(4x+7)2\frac{8 \left(- \frac{4 \left(x + 1\right)}{4 x + 7} + 1\right)}{\left(4 x + 7\right)^{2}}
The third derivative [src]
   /     4*(1 + x)\
96*|-1 + ---------|
   \      7 + 4*x /
-------------------
              3    
     (7 + 4*x)     
96(4(x+1)4x+71)(4x+7)3\frac{96 \cdot \left(\frac{4 \left(x + 1\right)}{4 x + 7} - 1\right)}{\left(4 x + 7\right)^{3}}
The graph
Derivative of -(x+1)/(4x+7)