Equations

• Quadratic formula:

  $ax^2+$$bx+$$c=$$0$
• Area of a circle:

  $A=$$πr^2$
• Circumference of a circle:

  $C=$$2πr$

  or

  $C=$$πd$
• Pythagoras Theorem:

  $a^2+$$b^2=$$c^2$
• Pythagoras Theorem:

  $a^2+$$b^2=$$c^2$

  
• Trigonometric ratios:

  $sinx°=$$opp/hyp$

  $cosx°=$$adj/hyp$

  $tanx°=$$opp/adj$

  
• Sine rule

  a/sin(A) = b/sin(B) = c/sin(C) { for finding sides}

  sin(A)/a = sin(B)/b = sin(C)/c {for finding angles} 


  Sine rule

  
• Cosine rule:

  a^2 = b^2 + c^2 −2bc cos(A) 

  
• Area of a triangle (trigonometry):

  Area= 1/2 ab sin C

  
• Volume of a prism:

  Volume= Area of cross section x length

  
• Volume of a pyramid:

  Volume= 1/3 x area of base x h

  
• Area of a parallelogram:

  Area= b x h

  
• Area of a triangle:

  Area= 1/2 b x h

  
• Area of a trapezium:

  Area= 1/2(a+b)h

  
• Speed= distance/time (m/s)
• Density= mass/volume (kg/cm^3)
• Pressure= force/area (N/m^2)
• Quadratic equation:

  $x=$$-b±√b^2-4ac/2a$


  .

  
• Arc length = θ/360 x πd
• Sampling

  (Sample number / population) x thing that your finding