IIT JEE , AIEEE Forum - Mathematics , Algebra - new list of formulae............!!!!!!!!!!!!!!!!!!!!

nivedh_89

i am starting a chain of formulae....................those who r interested , do post ur formulae too.....................they should b important and they should not be copied..................!!!!!!!!!!!!!!!!!!!!!!!!!!!!

nivedh_89

Polygon Formulas
(N = # of sides and S = length from center to a corner)

Area of a regular polygon = (1/2) N sin(360°/N) S²

Sum of the interior angles of a polygon = (N - 2) x 180°

The number of diagonals in a polygon = 1/2 N(N-3)
The number of triangles (when you draw all the diagonals from one vertex) in a polygon = (N - 2)

nivedh_89

Area Formulas

parallelogram = bh

trapezoid = h/2 (b₁ + b₂)

circle = pi r²

ellipse = pi r₁ r₂

nivedh_89

Volume Formulas

cube = a³

rectangular prism = a b c

irregular prism = b h

cylinder = b h = pi r² h

pyramid = (1/3) b h

cone = (1/3) b h = 1/3 pi r² h

sphere = (4/3) pi r³

ellipsoid = (4/3) pi r₁ r₂ r₃

nivedh_89

Surface Area of a Cube = 6 a²

(a is the length of the side of each edge of the cube)

In words, the surface area of a cube is the area of the six squares that cover it. The area of one of them is a*a, or a² . Since these are all the same, you can multiply one of them by six, so the surface area of a cube is 6 times one of the sides squared.

Surface Area of a Rectangular Prism = 2ab + 2bc + 2ac

(a, b, and c are the lengths of the 3 sides)

In words, the surface area of a rectangular prism is the are of the six rectangles that cover it. But we don't have to figure out all six because we know that the top and bottom are the same, the front and back are the same, and the left and right sides are the same.

The area of the top and bottom (side lengths a and c) = a*c. Since there are two of them, you get 2ac. The front and back have side lengths of b and c. The area of one of them is b*c, and there are two of them, so the surface area of those two is 2bc. The left and right side have side lengths of a and b, so the surface area of one of them is a*b. Again, there are two of them, so their combined surface area is 2ab.

Surface Area of Any Prism

(b is the shape of the ends)

Surface Area = Lateral area + Area of two ends

(Lateral area) = (perimeter of shape b) * L

Surface Area = (perimeter of shape b) * L+ 2*(Area of shape b)

nivedh_89

Surface Area of a Sphere = 4 pi r²

(r is radius of circle)

Surface Area of a Cylinder = 2 pi r² + 2 pi r h

(h is the height of the cylinder, r is the radius of the top)

Surface Area = Areas of top and bottom +Area of the side

Surface Area = 2(Area of top) + (perimeter of top)* height

Surface Area = 2(pi r²) + (2 pi r)* h

nivedh_89

***tan4x=4tanx(1-tan²x)/(1-6tan²x+tan⁴x)

***Area of the triangle made by the line ax+by+c=0 and the co ordinate axes is c²/(2ab)

***Area of the rhombus formed by ax+by+c=0 is 2c²/ab

***The foot of the perpendicular (h,k) from (x₁,y₁) to the line ax+by+c=0 is given by

(h-x₁)/a=(k-y₁)/b= -(ax₁+by₁+c)/(a²+b²)

nivedh_89

***The image or reflection of the point (x₁,y₁) in the line ax+by+c=0 is (h,k) where

(h-x₁)/a=(k-y₁)/b= -2(ax₁+by₁+c)/(a²+b²)

***The area bounded by y²=4ax andx²=4by is given by (4a)(4b)/3

***The area bounded by y²=4ax and the line y=mx is 8a²/(3m³)

***The area bounded by y²=4ax and its latus rectum x=a is 8a²/3

nivedh_89

plzzz comment.............................

beethoven

quit useful yaar...will u plz solve my problems,in algebra and analytical geometry

prashanth_prc

do not copy

nivedh_89

sure...................i will try my best............!!!!!!!!!!!!!!!!

Ask & Discuss Questions with Community & Experts

Area Formulas

parallelogram = bh

Volume Formulas