# REX05 Reducing Rational Expressions to Lowest Terms Part 1

In the previous video, we have learned about domain of rational functions. In this video, we are going to learn about how to reduce rational expressions particularly fractions to lowest terms.  Watch the Tagalog math tutorial video above and then answer the exercises below. The complete video playlist of the Sipnayan tutorials on Rational Expressions can be found here.

Practice Exercise

Reduce the following to lowest terms.

1.) $\dfrac{8}{12}$

2.) $\dfrac{15}{25}$.

3.) $\dfrac{9}{27}$.

4.) $\dfrac{6}{24}$.

5.) $latex \dfrac{10}{22}$.

1.) $\dfrac{2}{3}$

2.) $\dfrac{3}{5}$.

3.) $\dfrac{1}{3}$.

4.) $\dfrac{1}{4}$.

5.) $latex \dfrac{5}{11}$.

# REX03 Ruling Out the Values of the Variable

In the previous video, we have learned how to evaluate rational expressions. In this video, we are going to learn how to rule out the values of the variable in rational expressions. This concept is important because it is connected to the domain of rational functions  Watch the Tagalog math tutorial video above and then answer the exercises below. The complete video playlist of the Sipnayan tutorials on Rational Expressions can be found here.

Practice Exercise

Rule out the values of the variable of the following rational expressions.

1.) $\dfrac{x + 4}{x}$

2.) $\dfrac{2x - 1}{x + 2}$.

3.) $\dfrac{x^2 - 1}{2x + 5}$.

4.) $\dfrac{x^2 + 2x}{x^2 - 9}$.

5.) $\dfrac{x - 9}{x^2 - 5x + 4}$.

1. $x \neq 0$

2. $x \neq -2$

3. $x \neq -\frac{5}{2}$

4. $x \neq 3$, $x \neq -3$

5. $x \neq 1$, $x \neq 4$

# REX02 Evaluating Rational Expressions

In the previous video, we have learned about rational expressions. In this video, we learn how to evaluate rational expressions .  Watch the Tagalog math tutorial video above and then answer the exercises below. The complete video playlist of the Sipnayan tutorials on Rational Expressions can be found here.

Practice Exercise

Evaluate the following rational expressions.

1.)  If x = -2, find the value of

$\dfrac{3x - 1}{x - 4}$

2.) If y = 3, find the value of

$\dfrac{y^2 + 5y - 6}{5y + 1}$.

3.) The function $f(x) = \frac{2x + 5}{-x + 7}$ is a rational function. Find $f(0)$.

4.) If p = -4, q = 3, and r = 1, what is the value of

$\dfrac{p^2 - qr + q^2}{p - r}$

5.) If $x = \frac{1}{2}$, what is the value of

$\dfrac{4x - 1}{2x^2 + 1}$