Question 1094380
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<pre>
f(x) = 2x^3 + 2x^2 - 2x + 2   ==============>

f'(x) = 6x^2 + 4x - 2.


MinMax : f'(x) = 0  ====>  6x^2 + 4x - 2 = 0  ====>  3x^2 + 2x - 1 = 0  ====>


{{{x[1,2]}}} = {{{( -2 +- sqrt(2^2 + 4*3))/(2*3)}}} = {{{(-2 +- 4)/6}}};  ====>


{{{x[1]}}} = {{{(-2 + 4)/6}}} = {{{2/6}}} = {{{1/3}}}.


{{{x[2]}}} = {{{(-2 - 4)/6}}} = {{{-6/6}}} = -1.



{{{graph( 330, 330, -5.5, 5.5, -7.5, 7.5,
          2x^3 + 2x^2 - 2x + 2
)}}}


Plot y = 2x^3 + 2x^2 - 2x + 2
</pre>


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