Rational Expressions and Equations

Rational equations and expressions pertain to the ratios of polynomial expressions. Essentially, these are algebraic fractions where both the top and bottom components are polynomials. The process of solving these equations usually involves identifying a common denominator, streamlining or minimizing the expression, and equating the numerator to zero in order to solve for any unknown variables.

Reducing

Simplify the rational expression \( \frac{2x^2 - 5x - 3}{x^2 - 4} \)

Cancelling the Common Factors

Simplify the rational expression \( \frac{2x^2y^3}{4x^3y} \)

Rewriting in Standard Form

Rewrite the rational expression \(\frac{3x^2 + 5x - 2}{x^2 - 4}\) in standard form.

Operations on Rational Expressions

If \( f(x) = \frac{x^2 - 4x + 4}{x - 2} \), simplify \( f(x) \).

Determining if the Point is a Solution

Is the point (2,4) a solution to the equation \(y = \frac{{3x - 2}}{{x + 1}}\)?

Finding the Domain

Find the domain of the function \(f(x) = \frac{1}{x^2 - 4}\).

Solving over the Interval

Solve the given rational equation for \( x \) over the interval \( [0, 2\pi] \): \( \frac{1}{x} = \sin(x) \)

Finding the Range

Given the rational function \( f(x) = \frac{(x-1)}{(x+2)} \), find the range of \( f(x) \).

Finding the Domain and Range

Question 3 Let $f(x)=\frac{3 x-6}{x^{2}+8 x+15}=\frac{(3 x-6)}{(x+5)(x+3)}$ Find: 1) the domain in interval notation Note: Use -oo for $-\infty$, oo for $\infty$, U for union. 2) the $y$ intercept at the point 3) $x$ intercepts at the point(s) 4) Vertical asymptotes at $x=$ 5) Horizontal asymptote at $y=$

Solving Rational Equations

Solve the rational equation: \(\frac{2x}{x - 1} - \frac{3}{x} = 1\)

Adding Rational Expressions

2. $\frac{4 x^{2}-4 x-9}{(2 x+1)(x-1)} \equiv A+\frac{B}{2 x+1}+\frac{C}{x-1}$ a Find the values of the constants $A, B$ and $C$. b Hence, or otherwise, expand $\frac{4 x^{2}-4 x-9}{(2 x+1)(x-1)}$ in ascending powers of $x$, as far as the $x^{2}$ term c Explain why the expansion is not valid for $x=\frac{3}{4}$.

Subtracting Rational Expressions

Subtract the rational expressions \(\frac{5x}{x + 2}\) and \(\frac{3x}{x - 2}\)

Multiplying Rational Expressions

Multiply the following rational expressions: \(\frac{4x^{2}-9}{3x^{2}-5x+2}\) and \(\frac{2x-1}{2x^{2}+5x-3}\)

Finding the Equation Given the Roots

Find the equation of a polynomial given the roots are \(2\), \(-3\), and \(1\).

Finding the Asymptotes

Let $f(x)=\frac{3 x-6}{x^{2}+8 x+15}=\frac{(3 x-6)}{(x+5)(x+3)}$ Find: 3) $x$ intercepts at the point(s) 4) Vertical asymptotes at $x=-3$ 5) Horizontal asymptote at $y=-5$

Finding the Constant of Variation

If the variation equation is given as \(y = kx^2\), and the point \((2,8)\) lies on the graph of this equation, what is the constant of variation \(k\)?

Finding the Equation of Variation

If y varies directly with x, and y = 8 when x = 2, find the equation of variation.