How do you factor #z^3 - 125#?

1 Answer
Jan 24, 2017

Answer:

#(z-5)(z^2+5z+25)#

Explanation:

This is a #color(blue)"difference of cubes"# and factorises, in general, as shown.

#color(red)(bar(ul(|color(white)(2/2)color(black)(a^3-b^3=(a-b)(a^2+ab+b^2))color(white)(2/2)|)))#

#"here " (z)^3=z^3" and " (5)^3=125#

#rArra=z" and " b=5#

#rArrz^3-125=(z-5)(z^2+5z+25)#