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cos(pi(x+1))/2=-1 equation

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Numerical solution:

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The solution

You have entered [src]
cos(pi*(x + 1))     
--------------- = -1
       2            
$$\frac{\cos{\left(\pi \left(x + 1\right) \right)}}{2} = -1$$
Detail solution
Given the equation
$$\frac{\cos{\left(\pi \left(x + 1\right) \right)}}{2} = -1$$
- this is the simplest trigonometric equation
Divide both parts of the equation by -1/2

The equation is transformed to
$$\cos{\left(\pi x \right)} = 2$$
As right part of the equation
modulo =
True

but cos
can no be more than 1 or less than -1
so the solution of the equation d'not exist.
The graph
Rapid solution [src]
     I*im(acos(2))
x1 = -------------
           pi     
$$x_{1} = \frac{i \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi}$$
         I*im(acos(2))
x2 = 2 - -------------
               pi     
$$x_{2} = 2 - \frac{i \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi}$$
x2 = 2 - i*im(acos(2))/pi
Sum and product of roots [src]
sum
I*im(acos(2))       I*im(acos(2))
------------- + 2 - -------------
      pi                  pi     
$$\left(2 - \frac{i \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi}\right) + \frac{i \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi}$$
=
2
$$2$$
product
I*im(acos(2)) /    I*im(acos(2))\
-------------*|2 - -------------|
      pi      \          pi     /
$$\frac{i \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi} \left(2 - \frac{i \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi}\right)$$
=
(2*pi*I + im(acos(2)))*im(acos(2))
----------------------------------
                 2                
               pi                 
$$\frac{\left(\operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)} + 2 i \pi\right) \operatorname{im}{\left(\operatorname{acos}{\left(2 \right)}\right)}}{\pi^{2}}$$
(2*pi*i + im(acos(2)))*im(acos(2))/pi^2
Numerical answer [src]
x1 = 0.419200718278983*i
x2 = 2.0 - 0.419200718278983*i
x2 = 2.0 - 0.419200718278983*i