Essential Business Math Formulas & Concepts
Applied Business Mathematics Formulas
1. Polynomials, Exponents, and Roots
Exponent Rules:
- am ⋅ an = am+n
- (am)n = am⋅n
- a-n = 1/an
- am/an = am-n
Factoring Techniques:
- Common Factor: ab + ac = a(b + c)
- Difference of Squares: a2 – b2 = (a – b)(a + b)
- Quadratic Factorization: ax2 + bx + c = (px + q)(rx + s)
Quadratic Formula:
x = (-b ± √(b2 – 4ac)) / 2a
Example: Solving Quadratic Equations
- Solve x2 – 5x + 6 = 0
- Using the quadratic formula:
- x = (-(-5) ± √((-5)2 – 4(1)(6))) / 2(1)
- x = (5 ± 1) / 2
- Solutions: x = 3, x = 2
2. Set Theory Fundamentals
Set Notation:
- Union: A ∪ B (Elements in A or B)
- Intersection: A ∩ B (Elements in both A and B)
- Complement: Ac (Elements not in A)
- Cartesian Product: A × B (Pairs (a,b) with a ∈ A, b ∈ B)
Example: Set Operations
If A = {1,2,3}, B = {3,4,5}, then:
- A ∪ B = {1,2,3,4,5}
- A ∩ B = {3}
3. Sequences and Series
Arithmetic Sequences:
an = a1 + (n-1)d
- Sum: Sn = n/2 (a1 + an)
Example: Sum of Arithmetic Series
- Find sum of first 5 terms of 2, 4, 6, 8, 10
- S5 = 5/2 (2 + 10) = 30
Geometric Sequences:
an = a1 ⋅ r(n-1)
- Sum: Sn = a1(1 – rn) / (1 – r), |r| < 1
4. Interest and Amortization
Simple Interest:
A = P(1 + rt)
Compound Interest:
A = P(1 + r/n)nt
Amortization Formula:
A = Pr(1+r)n / ((1+r)n – 1)
Example: Future Value Calculation
Find the future value of 100€ at 4% interest over 3 years.
- A = 100(1 + 0.04/2)6
- Approximately 112.61€
5. Limits and Functions
Limit Laws:
- limx→a [f(x) + g(x)] = limx→a f(x) + limx→a g(x)
- limx→a [f(x)g(x)] = limx→a f(x) ⋅ limx→a g(x)
Example: Evaluating Limits
- Find limx→3 (x2 – 9) / (x – 3)
- Factor: (x – 3)(x + 3) / (x – 3)
- Cancel: Result: 6
6. Differentiation Principles
Differentiation Rules:
- Power Rule: d/dx xn = nxn-1
- Product Rule: (uv)’ = u’v + uv’
- Quotient Rule: (u/v)’ = (u’v – uv’) / v2
- Chain Rule: (f(g(x)))’ = f'(g(x))g'(x)
Example: Applying Power Rule
- Find d/dx (x3 + 2x)
- 3x2 + 2
7. Optimization and Extreme Values
Critical Points:
- f'(x) = 0
Optimization Tests:
- First Derivative Test: If f'(x) changes sign → max/min
- Second Derivative Test: f”(x) > 0 (min), f”(x) < 0 (max)
Example: Finding Maximum Value
- Find the maximum of f(x) = -x2 + 4x – 3
- f'(x) = -2x + 4, solve -2x + 4 = 0, x = 2
- f”(x) = -2 (negative, so maximum at x = 2)
- f(2) = -22 + 4(2) – 3 = 1, maximum is 1