Question

What is the justification for the first step in proving the formula for factoring the sum of cubes?

Answer 1

Answer:

Step-by-step explanation:

One approach would be to begin the indicated multiplication:  Multiply a² by a, obtaining a³, which is the first term of the product a3 – a2b + ab2 + a2b – ab2 + b3.  Please use " ^ " to indicate exponentiation, or (²) or (³):

a(a² - ab + b²) = a³ (plus 2 more terms, which are -a²b and ab²).  

Here we are applying the distributive property of multiplication.