How find the 3 value of x by using Calculator

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Hi all

How find the 3 value of x by using Calculator

u = 4x^3 - 4x = 0

I know this good way to solve iy

4x(x^2-1) = 0
X = 1 or X = -1 or X = 1

but I want a way bu useing a Calculator to find the 3 value of x

plese help me .
 
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The class of techniques are called root finding techniques and requires you to have something a little more hefty than a scientific calculator. Every calculator has a different layout so it's up to you to look up on google the instructions for your calculator to find out if or if not it has a "root finding" function.
 
r-soy said:
Hi all

How find the 3 value of x by using Calculator

u = 4x^3 - 4x = 0

I know this good way to solve iy

4x(x^2-1) = 0
X = 1 or X = -1 or X = 1
There are three different solutions to this equation, with none of them repeated.
r-soy said:
but I want a way bu useing a Calculator to find the 3 value of x

plese help me .
 
If you are using a graphing calculator, graph the function y= 4x^2- 4x and "zoom" in on the points where the graph crosses the y- axis.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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