Question 925531
{{{x^3-64=0}}}

{{{x^3-4^3=0}}}

{{{(x-4)(x^2+4x+16)=0}}}

one real root is: {{{x-4=0}}}=>{{{highlight(x=4)}}}

{{{(x^2+4x+16)=0}}}...use quadratic formula

{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}

{{{x = (-4 +- sqrt( 4^2-4*1*16 ))/(2*1) }}}

{{{x = (-4 +- sqrt( 16-64 ))/2 }}}

{{{x = (-4 +- sqrt( -48 ))/2 }}}

{{{x = (-4 +- sqrt( -16*3 ))/2 }}}

{{{x = (-cross(4)2 +- cross(4)2i*sqrt( 3 ))/cross(2) }}}

{{{x = -2 +- 2i*sqrt( 3 ) }}}

complex roots:

{{{highlight(x = -2 + 2i*sqrt( 3 )) }}}

{{{highlight(x = -2 - 2i*sqrt( 3 )) }}}


{{{ graph( 600, 600, -10, 10, -100, 70, x^3-64) }}}