College

Find the product:



[tex]7x^3\left(6x^2 - 4x\right)[/tex]



A. [tex]13x^6 - 11x^3[/tex]

B. [tex]13x^3 - 11x^4[/tex]

C. [tex]42x^5 - 28x^4[/tex]

D. [tex]42x^6 - 28x^3[/tex]

Answer :

- Distribute $7x^3$ to both terms inside the parenthesis: $7x^3 \times 6x^2 - 7x^3 \times 4x$.
- Simplify the first term: $7x^3 \times 6x^2 = 42x^5$.
- Simplify the second term: $7x^3 \times 4x = 28x^4$.
- The final expression is: $\boxed{42x^5 - 28x^4}$.

### Explanation
1. Understanding the problem
We are asked to find the product of the expression $7 x^3(6 x^2 - 4x)$. This involves distributing the term $7x^3$ to each term inside the parentheses.

2. Distributing the term
We distribute $7x^3$ to both terms inside the parenthesis: $7x^3 \times 6x^2 - 7x^3 \times 4x$.

3. Simplifying the expression
Now, we simplify each term by multiplying the coefficients and adding the exponents of $x$. For the first term, $7x^3 \times 6x^2 = (7 \times 6)x^{3+2} = 42x^5$. For the second term, $7x^3 \times 4x = (7 \times 4)x^{3+1} = 28x^4$. Therefore, the expression simplifies to $42x^5 - 28x^4$.

4. Choosing the correct option
Comparing our simplified expression $42x^5 - 28x^4$ with the given options, we see that it matches option C.

5. Final Answer
Therefore, the product of $7 x^3(6 x^2-4 x)$ is $42x^5 - 28x^4$.

### Examples
Understanding how to multiply polynomials is essential in various fields, such as engineering, physics, and computer graphics. For instance, when calculating the volume of a 3D object with polynomial dimensions or modeling physical phenomena with polynomial equations, polynomial multiplication is a fundamental operation. In computer graphics, it can be used to scale and transform objects.