# क्षेत्रफल आयतन: Maths: Area Volume Perimeter Formula : Short Tricks in Hindi क्षेत्रफल आयतन

## Maths: Area Volume Perimeter Formula : Short Tricks

In this post we share some most important formula of geometry related shapes. In this shape we are going to know how to calculate area, volume, surface area, circumference etc for square, rectangle, parallelogram, trapezoid, circle, ellipse, parabola etc geometries.

### Areas =  क्षेत्रफल

वर्ग square = a2
चतुर्भुज rectangle = ab
सामानांतर चतुर्भुज parallelogram = bh

चतुर्भुज trapezoid = h/2 (b1 + b2
वृत्त circle = pi r 2
दीर्घवृत्त ellipse = pi r1 r2
त्रिभुज triangle = (1/2) b h
समभुज त्रिकोण equilateral triangle = (1/4)(3) a2
यदि त्रिभुज में भुजा कोण भुजा दी हो तो triangle given SAS = (1/2) a b sin C
यदि तीन भुजा दी हो तो बिना बिना सम कोण में हेरो सूत्र   triangle given a,b,c = [s(s-a)(s-b)(s-c)] when s = (a+b+c)/2

(Heron's formula)
नियमित बहुभुज regular polygon = (1/2) n sin(360°/n) S2
when n = # of sides and S = length from center to a corner

### Volumes = आयतन

घन आयतन cube = a3
आयताकार rectangular prism = a b c
अनियमित irregular prism = b h
बेलन आयतन cylinder = b h =  r2 h
pyramid = (1/3) b h
शंकु आयतन cone = (1/3) b h = 1/3  r2 h
गोला आयतन  sphere = (4/3)  r3
परवलय आयतन ellipsoid = (4/3) pi r1 r2 r3

### Surface Areas

cube = 6 a2
prism:
(lateral area) = perimeter(b) L
(total area) = perimeter(b) L + 2b

sphere = 4  r2

## Circle:

Circumference of Circle = PI x diameter = 2 PI x radius
where PI =  = 3.141592...
Area of Circle:
area = PI r2
Length of a Circular Arc: (with central angle )
if the angle  is in degrees, then length =  x (PI/180) x r
if the angle  is in radians, then length = r x
Area of Circle Sector: (with central angle )
if the angle  is in degrees, then area = (/360) PI r2
if the angle  is in radians, then area = (/2) r2