fatorize : 8 a^3- b^3 -4a^2 - b2 +4ab
Answers
Step-by-step explanation:
STEP
1
:
Equation at the end of step 1
(((8•(a3))•(b2))-((44•(a2))•(b2)))-(22•3•7ab2)
STEP
2
:
Equation at the end of step
2
:
(((8•(a3))•(b2))-((22•11a2)•b2))-(22•3•7ab2)
STEP
3
:
Equation at the end of step
3
:
((23a3 • b2) - (22•11a2b2)) - (22•3•7ab2)
STEP
4
:
STEP
5
:
Pulling out like terms
5.1 Pull out like factors :
8a3b2 - 44a2b2 - 84ab2 = 4ab2 • (2a2 - 11a - 21)
Trying to factor by splitting the middle term
5.2 Factoring 2a2 - 11a - 21
The first term is, 2a2 its coefficient is 2 .
The middle term is, -11a its coefficient is -11 .
The last term, "the constant", is -21
Step-1 : Multiply the coefficient of the first term by the constant 2 • -21 = -42
Step-2 : Find two factors of -42 whose sum equals the coefficient of the middle term, which is -11 .
-42 + 1 = -41
-21 + 2 = -19
-14 + 3 = -11 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -14 and 3
2a2 - 14a + 3a - 21
Step-4 : Add up the first 2 terms, pulling out like factors :
2a • (a-7)
Add up the last 2 terms, pulling out common factors :
3 • (a-7)
Step-5 : Add up the four terms of step 4 :
(2a+3) • (a-7)
Which is the desired factorization
Final result :
4ab2 • (a - 7) • (2a + 3)