College

The quotient of [tex]\left(x^4+5x^3-3x-15\right)[/tex] and [tex]\left(x^3-3\right)[/tex] is a polynomial. What is the quotient?

A. [tex]x^7+5x^6-6x^4-30x^3+9x+45[/tex]
B. [tex]x-5[/tex]
C. [tex]x+5[/tex]
D. [tex]x^7+5x^6+6x^4+30x^3+9x+45[/tex]

Answer :

To solve the problem of finding the quotient of [tex]\(\left(x^4 + 5x^3 - 3x - 15\right)\)[/tex] divided by [tex]\(\left(x^3 - 3\right)\)[/tex], we can perform polynomial long division.

1. Setup the Division: We want to divide [tex]\(x^4 + 5x^3 - 3x - 15\)[/tex] by [tex]\(x^3 - 3\)[/tex].

2. Divide the Leading Terms:
- Divide the leading term of the dividend, [tex]\(x^4\)[/tex], by the leading term of the divisor, [tex]\(x^3\)[/tex].
- This gives [tex]\(x\)[/tex].

3. Multiply and Subtract:
- Multiply the whole divisor [tex]\(x^3 - 3\)[/tex] by [tex]\(x\)[/tex], resulting in [tex]\(x^4 - 3x\)[/tex].
- Subtract [tex]\(x^4 - 3x\)[/tex] from the dividend [tex]\(x^4 + 5x^3 - 3x - 15\)[/tex].
- After subtraction, the new polynomial is [tex]\(5x^3 + 0x^2 + 0x - 15\)[/tex].

4. Repeat the Process:
- Next, divide the leading term of the new polynomial, [tex]\(5x^3\)[/tex], by the leading term of the divisor, [tex]\(x^3\)[/tex].
- This gives [tex]\(+5\)[/tex].

5. Multiply and Subtract Again:
- Multiply the whole divisor [tex]\(x^3 - 3\)[/tex] by [tex]\(+5\)[/tex], resulting in [tex]\(5x^3 - 15\)[/tex].
- Subtract [tex]\(5x^3 - 15\)[/tex] from the current polynomial [tex]\(5x^3 + 0x^2 + 0x - 15\)[/tex].
- After subtraction, the remainder is [tex]\(0\)[/tex].

6. Conclusion:
- Once we get a remainder of 0, we have our quotient.
- So, the quotient of [tex]\(\left(x^4 + 5x^3 - 3x - 15\right)\)[/tex] divided by [tex]\(\left(x^3 - 3\right)\)[/tex] is [tex]\(x + 5\)[/tex].

Therefore, the quotient is [tex]\(x + 5\)[/tex].