Important PSAT Math Formulas?

Hi folks! I'm starting to study for the PSAT, and I was wondering if there's a list of key math formulas that I should definitely be familiar with. I want to make sure I've covered all the important ones before I start practicing problems. Thanks!

Hi there! It's smart to have a solid foundation of important math formulas before diving into PSAT practice problems. Here's a list of key formulas and concepts to help you prepare for the Math section of the PSAT:

1. Area and Perimeter Formulas:

- Rectangle: Area = length × width, Perimeter = 2 × (length + width)

- Square: Area = side², Perimeter = 4 × side

- Triangle: Area = 0.5 × base × height

- Circle: Area = π × radius², Circumference = 2 × π × radius

2. Pythagorean Theorem: For any right triangle, a² + b² = c² (where a and b are the legs, and c is the hypotenuse)

3. Quadratic Formula: For a quadratic equation in the form ax² + bx + c = 0, the solutions can be calculated using the formula x = (-b ± √(b² - 4ac)) / 2a

4. Slope-Intercept Form: For the equation of a straight line, y = mx + b (where m is the slope and b is the y-intercept)

5. Distance Formula: The distance between two points (x1, y1) and (x2, y2) is given by √((x2 - x1)² + (y2 - y1)²)

6. Midpoint Formula: The midpoint between two points (x1, y1) and (x2, y2) is given by ((x1 + x2) / 2, (y1 + y2) / 2)

7. Properties of Exponents:

- a^m × a^n = a^(m+n)

- (a^m) ^ n = a^(mn)

- a^m ÷ a^n = a^(m-n)

- a^0 = 1

8. Properties of Radicals:

- √(a × b) = √a × √b

- √(a ÷ b) = √a ÷ √b

- √(a^n) = a^(n/2) for even n, and √(a) = a^(1/2)

9. Combinations and Permutations Formulas:

- Combinations (order does not matter): C(n, r) = n! / (r!(n-r)!)

- Permutations (order matters): P(n, r) = n! / (n-r)!

10. Probability: Probability of an event = (Number of successful outcomes) / (Total number of possible outcomes)

11. Sum of the angles of a polygon with n sides: (n - 2) × 180°

12. Measures of Central Tendency: mean (average), median, and mode

13. Measures of Dispersion: range, interquartile range, variance, and standard deviation

This list is not exhaustive, but it should give you a solid foundation for the Math section of the PSAT. Make sure to practice applying these formulas and concepts through problem-solving to help you get comfortable using them. Good luck with your PSAT preparation!