How do you factor 8m^3 - 125n^38m3125n3?

2 Answers
May 16, 2018

(2m-5n)(4m^2+10mn+25n^2)(2m5n)(4m2+10mn+25n2)

Explanation:

"this is a "color(blue)"difference of cubes"this is a difference of cubes

"and factors in general as"and factors in general as

•color(white)(x)a^3-b^3=(a-b)(a^2+ab+b^2)xa3b3=(ab)(a2+ab+b2)

8m^3=(2m)^3rArra=2m8m3=(2m)3a=2m

125n^3=(5n)^3rArrb=5n125n3=(5n)3b=5n

8m^3-125n^3=(2m-5n)((2m)^2+(2mxx5n)+(5n)^2)8m3125n3=(2m5n)((2m)2+(2m×5n)+(5n)2)

color(white)(xxxxxxxxx)=(2m-5n)(4m^2+10mn+25n^2)××××x=(2m5n)(4m2+10mn+25n2)

May 16, 2018

(2m-5n) (4m^2 + 10mn + 25n^2)(2m5n)(4m2+10mn+25n2)

Explanation:

Remember that a^3-b^3=(a-b)(a^2+ab+b^2)a3b3=(ab)(a2+ab+b2)

8m^3-125n^3=2^3m^3-5^3n^3=(2m)^3-(5n)^38m3125n3=23m353n3=(2m)3(5n)3

Therefore, a=2m, b=5na=2m,b=5n

Sub in: (2m-5n) (4m^2 + 10mn + 25n^2)(2m5n)(4m2+10mn+25n2)