Mister Exam

Derivative of xsqrt(1-x)

Function f() - derivative -N order at the point
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The graph:

from to

Piecewise:

The solution

You have entered [src]
    _______
x*\/ 1 - x 
x1xx \sqrt{1 - x}
d /    _______\
--\x*\/ 1 - x /
dx             
ddxx1x\frac{d}{d x} x \sqrt{1 - x}
Detail solution
  1. Apply the product rule:

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

    f(x)=xf{\left(x \right)} = x; to find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

    1. Apply the power rule: xx goes to 11

    g(x)=1xg{\left(x \right)} = \sqrt{1 - x}; to find ddxg(x)\frac{d}{d x} g{\left(x \right)}:

    1. Let u=1xu = 1 - x.

    2. Apply the power rule: u\sqrt{u} goes to 12u\frac{1}{2 \sqrt{u}}

    3. Then, apply the chain rule. Multiply by ddx(1x)\frac{d}{d x} \left(1 - x\right):

      1. Differentiate 1x1 - x term by term:

        1. The derivative of the constant 11 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

      The result of the chain rule is:

      121x- \frac{1}{2 \sqrt{1 - x}}

    The result is: x21x+1x- \frac{x}{2 \sqrt{1 - x}} + \sqrt{1 - x}

  2. Now simplify:

    23x21x\frac{2 - 3 x}{2 \sqrt{1 - x}}


The answer is:

23x21x\frac{2 - 3 x}{2 \sqrt{1 - x}}

The graph
02468-8-6-4-2-1010-5050
The first derivative [src]
  _______        x     
\/ 1 - x  - -----------
                _______
            2*\/ 1 - x 
x21x+1x- \frac{x}{2 \sqrt{1 - x}} + \sqrt{1 - x}
The second derivative [src]
 /        x    \ 
-|1 + ---------| 
 \    4*(1 - x)/ 
-----------------
      _______    
    \/ 1 - x     
x4(1x)+11x- \frac{\frac{x}{4 \cdot \left(1 - x\right)} + 1}{\sqrt{1 - x}}
The third derivative [src]
   /      x  \
-3*|2 + -----|
   \    1 - x/
--------------
          3/2 
 8*(1 - x)    
3(x1x+2)8(1x)32- \frac{3 \left(\frac{x}{1 - x} + 2\right)}{8 \left(1 - x\right)^{\frac{3}{2}}}
The graph
Derivative of xsqrt(1-x)