How do you factor #27r^3 + 125s^3#?
2 Answers
May 14, 2018
Explanation:
#"this is a "color(blue)"sum of cubes"#
#"which factors in general as"#
#•color(white)(x)a^3+b^3=(a+b)(a^2-ab+b^2)#
#27r^3=(3r)^3rArra=3r#
#125s^3=(5s)^3rArrb=5s#
#rArr27r^3+125s^3#
#=(3r+5s)((3r)^2-(3rxx5s)+(5s)^2)#
#=(3r+5s)(9r^2-15rs+25s^2)#
May 14, 2018
Explanation:
show below
Note that