SOLUTION: x to the 3rd power -64=0

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: x to the 3rd power -64=0       Log On


   

Question 925531: x to the 3rd power -64=0
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E3-64=0
x%5E3-4%5E3=0
%28x-4%29%28x%5E2%2B4x%2B16%29=0
one real root is: x-4=0=>highlight%28x=4%29
%28x%5E2%2B4x%2B16%29=0...use quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-4+%2B-+sqrt%28+4%5E2-4%2A1%2A16+%29%29%2F%282%2A1%29+
x+=+%28-4+%2B-+sqrt%28+16-64+%29%29%2F2+
x+=+%28-4+%2B-+sqrt%28+-48+%29%29%2F2+
x+=+%28-4+%2B-+sqrt%28+-16%2A3+%29%29%2F2+
x+=+%28-cross%284%292+%2B-+cross%284%292i%2Asqrt%28+3+%29%29%2Fcross%282%29+
x+=+-2+%2B-+2i%2Asqrt%28+3+%29+
complex roots:
highlight%28x+=+-2+%2B+2i%2Asqrt%28+3+%29%29+
highlight%28x+=+-2+-+2i%2Asqrt%28+3+%29%29+

+graph%28+600%2C+600%2C+-10%2C+10%2C+-100%2C+70%2C+x%5E3-64%29+