# REX01 Introduction to Rational Expressions

In this video, we learn the definition of rational numbers, rational expressions, and 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

True or False

1.)  The fraction $\frac{\pi}{3}$ is a rational number.

2.) The fraction $\frac{2x - 1}{5x + 1}$ is a rational expression.

3.) The fraction $\frac{\sqrt{x} + 3}{x^2 + 3}$ is a rational expression.

4.) The function $f(x) = \frac{1}{x}$ is a rational function.

5.) The fraction $\frac{3}{8}$ is a rational number.

1.False. The numerator and denominator of a rational number must be integers.
2. True
3. False. $\sqrt{x} + 3$ is not a polynomial expression.
4. True
5. True

# Paano gawin ang addition ng integers gamit ang number line?

Pag tayo ay nag-add ng number, ang representation nito sa number line ay ang paggalaw papuntang kanan. Pag tayo ay nagsubtract (o nag-add ng negative number), ang represenation nito ay ang paggalawa pakaliwa.

Ang number line ay isa lamang sa mga representations na pwede nating tingnan kung tayo ay naga-add ng integers. Panoorin ang video sa itaas upang maintindihan ang nangyayari sa addition ng integers.

Pwede mapanood ang mga tagalog math video tutorials tungkol sa integers (kasama addition of integers) ng tuloy tuloy sa Youtube (25 videos).

# Paano i-prove ang Pythagorean Theorem?

This Taglish (mixed Tagalog and English) math tutorial video discusses the proof of the Pythagorean Theorem.

The Pythagorean Theorem states the sum of the squares of the length of the shorter side of a right triangle is equal to the square of its hypotenuse. That is, in a right triangle with sides $a$ and $b$ and hypotenuse $c$, then $c^2 = a^2 + b^2$.

# Paano mag-subtract ng fractions?

This video tutorial discusses subtraction of fractions.  The examples discussed in this video include similar fractions, dissimilar fractions, and mixed fractions.

Subtracting fractions is very similar to adding fractions. For similar fractions, the numerator are subtracted and the numerator copied in the answer. For dissimilar fractions, least common multiple is needed in order to perform the operation.