How do you solve 2x^3-8x=02x38x=0 by factoring?

1 Answer
Oct 6, 2015

x=0color(white)(XXX")x=0XXX or
x=-2color(white)("XX")x=2XX or
x=+2x=+2

Explanation:

2x^3-8x=02x38x=0

rarrcolor(white)("XXX")(2)(x)(x^2-4)=0XXX(2)(x)(x24)=0

rarrcolor(white)("XXX")(2)(x)(x+2)(x-2)=0XXX(2)(x)(x+2)(x2)=0

rarrcolor(white)("XXX")x=0color(white)("XX")or color(white)("XX")x+2=0color(white)("XXX")orcolor(white)("XX")x-2=0XXXx=0XXorXXx+2=0XXXorXXx2=0

rarrcolor(white)("XXX")x=0color(white)("XX")orcolor(white)("XX")x=-2color(white)("XXXX")orcolor(white)("XX")x=+2XXXx=0XXorXXx=2XXXXorXXx=+2