Essential Mathematics and Statistics Formula Sheet

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Quick revision table for Mathematics and Statistics exams.

Unit I: Integration and Data Presentation

TopicFormulaUse
Integration Algebraic∫xⁿ dx = xⁿ⁺¹/(n+1) + C, n≠-1
∫1/x dx = ln|x| + C
∫k dx = kx + C
∫x dx = x²/2 + C
Finding area, antiderivative
Integration Trigonometric∫sin x dx = -cos x + C
∫cos x dx = sin x + C
∫sec²x dx = tan x + C
∫tan x dx = ln|sec x| + C
∫cot x dx = ln|sin x| + C
Trig integration
Integration Exponential∫eˣ dx = eˣ + C
∫aˣ dx = aˣ/ln a + C
Growth, decay problems
Pie Diagram AngleAngle of sector = (Component value / Total value) × 360°Constructing pie chart
Median from OgiveMedian = X-coordinate of intersection point of "less than" and "more than" ogiveGraphical method

Unit II: Central Tendency and Dispersion

TopicFormulaNote
Arithmetic Mean Ungroupedx̄ = Σx / nn = number of observations
Arithmetic Mean Groupedx̄ = Σfx / Σff = frequency, x = mid-value
Median Ungrouped (Odd n)Median = [(n+1)/2]th termData must be sorted
Median Ungrouped (Even n)Median = [n/2 th term + (n/2+1)th term] / 2Average of 2 middle terms
Median GroupedMedian = L + [(N/2 - cf)/f] × hL=lower limit, N=Σf, cf=cum freq before, f=freq of median class, h=class width
Mode GroupedMode = L + [(f1-f0)/(2f1-f0-f2)] × hf1=freq of modal class, f0=freq before, f2=freq after
Geometric MeanGM = (x₁·x₂·...·xₙ)¹/ⁿ or log GM = (Σlog x) / nUsed for average growth rate
Harmonic MeanHM = n / Σ(1/xᵢ)Used for average speed
RangeRange = Maximum value - Minimum valueSimplest measure
Mean DeviationM.D. = Σ|x - x̄| / n; Coefficient of M.D. = M.D. / x̄x̄ = mean used
Variance Populationσ² = Σ(x - x̄)² / nn = total frequency
Standard Deviationσ = √[Σ(x - x̄)² / n]Most reliable measure
Coefficient of VariationC.V. = (σ / x̄) × 100%Used to compare 2 datasets

Unit III: Correlation

TopicFormulaRange/Note
Karl Pearson's Coefficient rr = Σ[(X-x̄)(Y-ȳ)] / √[Σ(X-x̄)² × Σ(Y-ȳ)²]
Shortcut: r = [ΣXY - n·x̄·ȳ] / √[ΣX²-n·x̄²][ΣY²-n·ȳ²]
-1 ≤ r ≤ +1; r=+1 perfect positive, r=-1 perfect negative, r=0 no correlation
Spearman's Rank Correlationrₛ = 1 - [6ΣD² / n(n²-1)]D = difference in ranks; Used for ranked/qualitative data

Unit IV: Linear Regression

TopicFormulaUse
Regression Equation Y on XY = a + b_yx·X
b_yx = r·(σy/σx) = Σ[(X-x̄)(Y-ȳ)]/Σ(X-x̄)²
a = ȳ - b_yx·x̄
Predict value of Y for given X
Regression Equation X on YX = a' + b_xy·Y
b_xy = r·(σx/σy) = Σ[(X-x̄)(Y-ȳ)]/Σ(Y-ȳ)²
a' = x̄ - b_xy·ȳ
Predict value of X for given Y
Relation between r and br = ±√(b_yx × b_xy)r is geometric mean of regression coefficients
Principle of Least SquaresMinimize Σ(Y - Ŷ)²Condition for line of best fit

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