← Back

📋 Formula Sheet

📐Basic Shapes

Rectangle Area

A=l×wA = l \times w

Length × Width

Rectangle Perimeter

P=2(l+w)P = 2(l + w)

2 × (Length + Width)

Triangle Area

A=12×b×hA = \frac{1}{2} \times b \times h

Half × Base × Height

Square Area

A=s2A = s^2

Side × Side

Circles

Circumference

C=πd=2πrC = \pi d = 2\pi r

π × diameter or 2π × radius

Area of Circle

A=πr2A = \pi r^2

π × radius²

Arc Length

l=θ360×2πrl = \frac{\theta}{360} \times 2\pi r

Fraction of circumference

Sector Area

A=θ360×πr2A = \frac{\theta}{360} \times \pi r^2

Fraction of circle area

🔢Algebra

Difference of Squares

a2b2=(a+b)(ab)a^2 - b^2 = (a+b)(a-b)

Factorising pattern

Perfect Square (add)

(a+b)2=a2+2ab+b2(a+b)^2 = a^2 + 2ab + b^2

Expanding brackets

Perfect Square (subtract)

(ab)2=a22ab+b2(a-b)^2 = a^2 - 2ab + b^2

Expanding brackets

Quadratic Formula

x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2-4ac}}{2a}

Solves ax² + bx + c = 0

📈Straight Lines

Equation of a Line

y=mx+cy = mx + c

m = gradient, c = y-intercept

Gradient

m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}

Change in y ÷ Change in x

Midpoint

(x1+x22,y1+y22)\left(\frac{x_1+x_2}{2}, \frac{y_1+y_2}{2}\right)

Average of coordinates

Distance

d=(x2x1)2+(y2y1)2d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}

Using Pythagoras

📊Pythagoras & Trigonometry

Pythagoras Theorem

a2+b2=c2a^2 + b^2 = c^2

For right-angled triangles

SOH CAH TOA

sinθ=OH,cosθ=AH,tanθ=OA\sin\theta = \frac{O}{H}, \cos\theta = \frac{A}{H}, \tan\theta = \frac{O}{A}

Trigonometric ratios

Sine Rule

asinA=bsinB=csinC\frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C}

For any triangle

Cosine Rule

a2=b2+c22bccosAa^2 = b^2 + c^2 - 2bc\cos A

For any triangle

Area of Triangle (Trig)

A=12absinCA = \frac{1}{2}ab\sin C

Using two sides and included angle

📦Volume & Surface Area

Cuboid Volume

V=l×w×hV = l \times w \times h

Length × Width × Height

Prism Volume

V=A×hV = A \times h

Cross-section area × Height

Cylinder Volume

V=πr2hV = \pi r^2 h

π × radius² × height

Cone Volume

V=13πr2hV = \frac{1}{3}\pi r^2 h

⅓ × π × radius² × height

Sphere Volume

V=43πr3V = \frac{4}{3}\pi r^3

⁴⁄₃ × π × radius³

Sphere Surface Area

A=4πr2A = 4\pi r^2

4 × π × radius²

📊Statistics

Mean

xˉ=xn\bar{x} = \frac{\sum x}{n}

Sum of values ÷ Number of values

Mean (Frequency)

xˉ=fxf\bar{x} = \frac{\sum fx}{\sum f}

For grouped data

Probability

P(A)=favourable outcomestotal outcomesP(A) = \frac{\text{favourable outcomes}}{\text{total outcomes}}

Basic probability

Compound Measures

Speed

S=DTS = \frac{D}{T}

Distance ÷ Time

Density

D=MVD = \frac{M}{V}

Mass ÷ Volume

Pressure

P=FAP = \frac{F}{A}

Force ÷ Area

💡 Tip: Press Ctrl/Cmd + P to print this page for revision