SAT Prep – Math: Advanced Math
DSAT Math Content: Advanced Math Domain
This domain covers linear equations, inequalities, and systems. Students analyze relationships between variables, manipulate algebraic expressions, and solve equations efficiently.
Core Skills
- Solve quadratic equations (factored, vertex, or standard form)
- Work with exponential models
- Perform polynomial operations (add, subtract, multiply)
- Solve rational equations and analyze restrictions
- Interpret function graphs and key features
- Understand function notation and composition
Example
If the roots of a quadratic equation $ax^2+bx+c=0$ are reciprocal to each other, which of the following is necessarily true? (Without calculator)
- $a=b$
- $a=c$
- $b=0$
- $c=-a$
Solution
We know that the product of the roots of a quadratic equation $ax^2 + bx + c=0$ is equal to $\frac{c}{a}$.
Given: the roots are reciprocal to each other.
Let's assume that the roots are $\alpha$ and $\frac{1}{\alpha}$.
So, product of the roots = $\alpha \times \frac{1}{\alpha}=\frac{c}{a}$
$=>1=\frac{c}{a}$
$=>c=a$
The correct answer is option B.
Applications
- Growth and decay models
- Projectile motion
- Revenue, profit, and optimization
- Chemical reaction rate modeling
Tools on DSAT
- Graph visualization for nonlinear behavior
- Ability to check solutions by graphing lines