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4 votes
Factor completely.

20x3 + 12x2 + 5x+3
O A. (2x + 1)(5x+3)
OB. (2x + 3)(5x+3)
OC. (4x2 + 1)(x+3)
OD. (4x2 + 1)(5x+3)

Factor completely. 20x3 + 12x2 + 5x+3 O A. (2x + 1)(5x+3) OB. (2x + 3)(5x+3) OC. (4x-example-1
User Mikerobi
by
6.2k points

1 Answer

4 votes

Answer:(5x+3)(4x2+1)

Explanation:

20x3-12x2+5x-3

Final result :

(4x2 + 1) • (5x - 3)

Reformatting the input :

Changes made to your input should not affect the solution:

(1): "x2" was replaced by "x^2". 1 more similar replacement(s).

Step by step solution :

Step 1 :

Equation at the end of step 1 :

(((20 • (x3)) - (22•3x2)) + 5x) - 3

Step 2 :

Equation at the end of step 2 :

(((22•5x3) - (22•3x2)) + 5x) - 3

Step 3 :

Checking for a perfect cube :

3.1 20x3-12x2+5x-3 is not a perfect cube

Trying to factor by pulling out :

3.2 Factoring: 20x3-12x2+5x-3

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

Group 1: 5x-3

Group 2: 20x3-12x2

Pull out from each group separately :

Group 1: (5x-3) • (1)

Group 2: (5x-3) • (4x2)

-------------------

Add up the two groups :

(5x-3) • (4x2+1)

Which is the desired factorization

Polynomial Roots Calculator :

3.3 Find roots (zeroes) of : F(x) = 4x2+1

Polynomial Roots Calculator is a set of methods aimed at finding values of x for which F(x)=0

Rational Roots Test is one of the above mentioned tools. It would only find Rational Roots that is numbers x which can be expressed as the quotient of two integers

The Rational Root Theorem states that if a polynomial zeroes for a rational number P/Q then P is a factor of the Trailing Constant and Q is a factor of the Leading Coefficient

In this case, the Leading Coefficient is 4 and the Trailing Constant is 1.

The factor(s) are:

of the Leading Coefficient : 1,2 ,4

of the Trailing Constant : 1

Let us test ....

P Q P/Q F(P/Q) Divisor

-1 1 -1.00 5.00

-1 2 -0.50 2.00

-1 4 -0.25 1.25

1 1 1.00 5.00

1 2 0.50 2.00

1 4 0.25 1.25

Polynomial Roots Calculator found no rational roots

Final result :

(4x2 + 1) • (5x - 3)

User Ahmad Nassri
by
6.2k points