Select all correct factorizations of [tex]27 x^6 - 45 x^4 + 63 x^2[/tex].

A. [tex]9 x^2\left(3 x^4 - 5 x^2 + 7\right)[/tex]
B. [tex]9 x^2 \left(3 x^4 - 5 x^2 + 7\right)[/tex]
C. [tex]9 x^2 \cdot 3 x^4 - 9 x^2 \cdot 5 x^2 + 9 x^2 \cdot 7[/tex]
D. [tex]3 x^2\left(9 x^4 - 15 x^2 + 21\right)[/tex]



Answer :

To determine the correct factorizations of the polynomial [tex]\( 27x^6 - 45x^4 + 63x^2 \)[/tex], let’s examine each provided form and verify their correctness.

1. Factor form: [tex]\( 9x^2\left( 3x^4 - 5x^2 + 7 \right) \)[/tex]
- To verify, we can expand this expression:
[tex]\[ 9x^2 \cdot (3x^4 - 5x^2 + 7) = 9x^2 \cdot 3x^4 + 9x^2 \cdot (-5x^2) + 9x^2 \cdot 7 \][/tex]
Simplifying each term individually:
[tex]\[ 9x^2 \cdot 3x^4 = 27x^6 \][/tex]
[tex]\[ 9x^2 \cdot (-5x^2) = -45x^4 \][/tex]
[tex]\[ 9x^2 \cdot 7 = 63x^2 \][/tex]
Therefore, the expanded form is:
[tex]\[ 27x^6 - 45x^4 + 63x^2 \][/tex]
This matches the given polynomial, so this factorization is correct.

2. Factor form: [tex]\( 9x^2 \left( 3x^4 - 5x^2 + 7 \right) \)[/tex]
- This is identical to the first factor form we verified and is also correct for the reasons given above.

3. Factor form: [tex]\( 9x^2 \cdot 3x^4 - 9x^2 \cdot 5x^2 + 9x^2 \cdot 7 \)[/tex]
- To verify, we can expand this expression:
[tex]\[ 9x^2 \cdot 3x^4 - 9x^2 \cdot 5x^2 + 9x^2 \cdot 7 = 27x^6 - 45x^4 + 63x^2 \][/tex]
This matches the given polynomial directly. Thus, this factorization is also correct.

4. Factor form: [tex]\( 3x^2 \left( 9x^4 - 15x^2 + 21 \right) \)[/tex]
- To verify, we can expand this expression:
[tex]\[ 3x^2 \cdot (9x^4 - 15x^2 + 21) = 3x^4 \cdot 9x^4 + 3x^2 \cdot (-15x^2) + 3x^2 \cdot 21 \][/tex]
Simplifying each term individually:
[tex]\[ 3x^2 \cdot 9x^4 = 27x^6 \][/tex]
[tex]\[ 3x^2 \cdot (-15x^2) = -45x^4 \][/tex]
[tex]\[ 3x^2 \cdot 21 = 63x^2 \][/tex]
Therefore, the expanded form is:
[tex]\[ 27x^6 - 45x^4 + 63x^2 \][/tex]
This matches the given polynomial, so this factorization is also correct.

Conclusion:
All provided factor forms match the given polynomial when expanded. Thus, the correct factorizations are:
[tex]\[ 9x^2 (3x^4 - 5x^2 + 7), \quad 9x^2 (3x^4 - 5x^2 + 7), \quad 9x^2 \cdot 3x^4 - 9x^2 \cdot 5x^2 + 9x^2 \cdot 7, \quad 3x^2 (9x^4 - 15x^2 + 21) \][/tex]

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