Question 1

In a direct current circuit, voltage equals current (I) times resistance (R). If the current in a circuit is 2 Amperes and the resistance is represented by the function [tex]R=\frac{x^2-x-30}{2x-12}[/tex] Ohms, what is the simplified function that represents the voltage?

A. [tex]x[/tex] Volts
B. [tex]x+5[/tex] Volts
C. [tex]x-6[/tex] Volts
D. [tex]x-5[/tex] Volts



Answer :

To find the function that represents the voltage in the given circuit, we need to follow these steps:

1. Identify the parameters:
- Current ([tex]\(I\)[/tex]) is 2 Amperes.
- Resistance ([tex]\(R\)[/tex]) is represented by the function [tex]\(\frac{x^2 - x - 30}{2x - 12}\)[/tex] Ohms.

2. Simplify the resistance function [tex]\(R\)[/tex]:
[tex]\[ R = \frac{x^2 - x - 30}{2x - 12} \][/tex]

First, factorize the numerator [tex]\(x^2 - x - 30\)[/tex]:
[tex]\[ x^2 - x - 30 = (x - 6)(x + 5) \][/tex]

This allows us to rewrite the resistance function as:
[tex]\[ R = \frac{(x - 6)(x + 5)}{2x - 12} \][/tex]

Notice that the denominator [tex]\(2x - 12\)[/tex] can be factored out as:
[tex]\[ 2x - 12 = 2(x - 6) \][/tex]

Therefore, the resistance function can be further simplified by cancelling out [tex]\(x - 6\)[/tex] from the numerator and denominator:
[tex]\[ R = \frac{(x - 6)(x + 5)}{2(x - 6)} = \frac{x + 5}{2} \][/tex]

So, the simplified resistance function [tex]\(R\)[/tex] is:
[tex]\[ R = \frac{x}{2} + \frac{5}{2} \][/tex]

3. Calculate the voltage [tex]\(V\)[/tex] using the formula [tex]\(V = I \times R\)[/tex]:

Since the current [tex]\(I\)[/tex] is 2 Amperes, substitute [tex]\(I = 2\)[/tex] into the voltage formula:
[tex]\[ V = 2 \times \left(\frac{x}{2} + \frac{5}{2}\right) \][/tex]

Distribute the 2:
[tex]\[ V = 2 \times \frac{x}{2} + 2 \times \frac{5}{2} \][/tex]
This simplifies to:
[tex]\[ V = x + 5 \][/tex]

So, the function that represents the voltage in the circuit is:

[tex]\[ \boxed{x + 5 \text{ Volts}} \][/tex]