(21x^3 - 7)/(3x - 1)(this one I cant get the anwswer to match up with my answer choices.)

Is there a way that I could use syntheic division?

what do you get?

7(3x^3-4)

Yes, you can use synthetic division to simplify the expression (21x^3 - 7) / (3x - 1) and potentially find the answer. Here is how you can do it:

Step 1: Write down the coefficients of the dividend (21x^3 - 7) in descending order of powers of x. In this case, the coefficients are 21, 0, 0, and -7.

Step 2: Set up the synthetic division by writing the divisor (3x - 1) to the left of the coefficients.

3x - 1 | 21 0 0 -7

Step 3: Bring down the first coefficient (21) and multiply it by the divisor (3x - 1). Write the result below the second coefficient.

3x - 1 | 21 0 0 -7
63x - 21

Step 4: Add the second coefficient to the result obtained in Step 3.

3x - 1 | 21 0 0 -7
63x - 21
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21 63 0 -7

Step 5: Repeat Steps 3 and 4 until you have gone through all the coefficients.

3x - 1 | 21 0 0 -7
63x - 21
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21 63 0 -7
63 0 0
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21 0 0 -7 0

Step 6: The remainders in the last row of the synthetic division are the coefficients of the simplified polynomial (21x^3 - 7) / (3x - 1).

In this case, the simplified polynomial is 21x^2 + 63 + (-7) / (3x - 1), which can be further simplified to (21x^2 + 56) / (3x - 1).

Make sure to double-check your work and see if this matches any of your answer choices.