How do you factor: #y= 27x^3 - 1 #?
2 Answers
Jan 18, 2016
Explanation:
Cube root of 27 is 3 and the cube root of -1 is also -1.
To factor
remember that
substituting,
Jan 18, 2016
Explanation:
Notice that both the terms are cubed terms, i.e.
That means that this is a difference of cubes, which can be factored as follows;
#a^3-b^3=(a-b)(a^2+ab+b^2)#
Thus, we have
#27x^3-1=(3x)^3-1^3#
#=(3x-1)((3x)^2+(3x)(1)+1^2)#
#=(3x-1)(9x^2+3x+1)#