Math formulae:.........

Good Math softwares, websites: Matlab, Mathematica, Maple, Symbolab, CAS, Wolfram
PEMDAS: Parenthesis, Exponential, Multiplication, Division, Addition, Subtraction
BODMAS: Brackets, Orders (powers and roots), Division and Multiplication, Addition and Subtraction
Identities(Additive, Associative,Multiplicative, Distributive, Commutative, polynomial)

(a+b)^2 = a^2 + 2ab + b^2
(a+b)(c+d) = ac + ad + bc + bd
#Difference of squares
a^2 - b^2 = (a+b)(a-b)
#Sum and Difference of Cubes
a^3 (+-) b^3 = (a (+-) b)(a^2(-+) ab + b^2)
#Quadratic Formula
ax^2 + bx + c = 0 then x = ( -b (+-)sqrt(b^2 - 4ac) ) / 2a
------------------------------
########Mensuration########
pi = 3.141
#Circle
Circumference = 2Pi r
Area = Pi r^2

Length of arc
    = theta (in degree)  (Pi/180)  r
    = theta (in radian) r

Area of Sector:
= (theta/360) Pi r^2  
=((theta/(2Pi)) Pi r^2

#Surface Area formulae
Cube = 6a^2
Cylinder = 2pi r^2 + 2pi rh
Sphere = 4 pi r^2

#Volume formulae
cube = a^3
rectangular prism = abc
cylinder = pi r^2h
cone = (1/3)pi r^2h
sphere = (4/3) pi r^3

########Trigonometry########
sin(q) = opposite / hypotenuse = p/h
cos(q) = base / hypotenuse = b/h
sin(90°) = 1
cos(90°) = 0