Question

Factorise 8a3+72a2-216a+216​

Answer 1

Answer:

Step-by-step explanation:

Final result :

8 • (a3 + 9a2 - 27a + 27)

Step by step solution :

Step 1 :

Equation at the end of step 1 :

(((8 • (a3)) + (23•32a2)) - 216a) + 216

Step 2 :

Equation at the end of step 2 :

((23a3 + (23•32a2)) - 216a) + 216

Step 3 :

Step 4 :

Pulling out like terms :

4.1 Pull out like factors :

8a3 + 72a2 - 216a + 216 =

8 • (a3 + 9a2 - 27a + 27)

Checking for a perfect cube :

4.2 a3 + 9a2 - 27a + 27 is not a perfect cube

Trying to factor by pulling out :

4.3 Factoring: a3 + 9a2 - 27a + 27

Thoughtfully split the expression at hand into groups, each group having two terms :

Group 1: a3 + 27

Group 2: -27a + 9a2

Pull out from each group separately :

Group 1: (a3 + 27) • (1)

Group 2: (a - 3) • (9a)