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 :

- Factor the numerator by grouping: $x^4+5x^3-3x-15 = (x^3-3)(x+5)$.
- Rewrite the expression as $\frac{(x^3-3)(x+5)}{x^3-3}$.
- Cancel the common factor $x^3-3$.
- The quotient is $\boxed{x+5}$.

### Explanation
1. Understanding the Problem
We are given the expression $\frac{x^4+5x^3-3x-15}{x^3-3}$ and we want to find the quotient, assuming it is a polynomial.

2. Factoring the Numerator
We can try to factor the numerator to see if $x^3-3$ is a factor. We can use factoring by grouping: $$x^4+5x^3-3x-15 = x^3(x+5) - 3(x+5) = (x^3-3)(x+5)$$.

3. Rewriting the Expression
Now we can rewrite the expression as: $$\frac{x^4+5x^3-3x-15}{x^3-3} = \frac{(x^3-3)(x+5)}{x^3-3}$$.

4. Simplifying the Expression
Since $x^3-3$ is a factor of the numerator, we can cancel it out, which gives us: $$\frac{(x^3-3)(x+5)}{x^3-3} = x+5$$.

5. Final Answer
Therefore, the quotient is $x+5$.

### Examples
Polynomial division is used in various engineering and scientific applications, such as designing control systems, analyzing circuits, and modeling physical phenomena. For example, when designing a bridge, engineers use polynomial functions to model the load distribution and structural integrity. Dividing these polynomials helps them determine critical parameters and ensure the bridge's stability under different conditions.