Formulas

The skmtutorial.blogspot.com is created for the help of CBSE school's classes of I, II, III, IV, V, VI, VII, VIII, IX, X classes. The Blog contains maths helpful formulas which are beneficial for all the CBSE Secondary classes.

Algebraic Identities

a²-b²=(a-b)(a+b);

(a+b)²=a²+b²+2ab;

(a-b)²=a²+b²-2ab;

(x+a)(x+b)= x²+ (a+b)x+ab;

(x+y+z)²=x²+y²+z²+2xy+2yz+2zx;

(x+y)³=x³+y³+3xy(x+y);

(x-y)³=x³-y³-3xy(x-y);

X³+y³+z³-3xyz=(x+y+z)(x²+y²+z²-xy-yz-zx);

Circumference and Area

Square

Perimeter of a Square=4*side;

Area of a Square=side*side;

Rectangle

Perimeter of a Rectangle=2*(length + breadth);

Area of a Rectangle=length*breadth;

Circle

Radius of a Circle=r;

Diameter of a Circle=d;

Π=22/7;

Circumference of a Circle=2πr;

Area of a Circle=πr²;

Triangle

Perimeter of a Triangle=Sum of all three sides of a Triangle;

Area of a Triangle=1/2*Base*Height;

Perimeter of a Parallelogram=Sum of all four sides of a Parallelogram;

Area of a Parallelogram=Base*Height;

Curved Surface area of a Cuboid=2*(Length+Breadth)*Height;

Total Surface area of a Cuboid= 2*(Length*Breadth+Breadth*Height+Height*Length);

Volume of a Cuboid=Length*Breadth*Height;

Curved Surface area of a Cube=4*Side²;

Total Surface area of a Cube=6*Side²;

Volume of a Cube=Length*Breadth*Height;

Curved Surface area of a Circular Cylinder=2πrh;

Total Surface area of a Circular Cylinder=2πrh+ πr²+ πr²

                                        =2πrh+2πr²

                                        =2πr(r+h);

Volume of a Circular Cylinder=πr²h;

Curved Surface area of a Cone=πrl;

Total Surface area of a Cone=πrl+πr²= πrl (l+r);

Volume of a Cone=1/3 πr²h;

Volume of a Sphere=4/3 πr³;

Curved Surface Area of a Hemisphere=2πr²;

Total Surface Area of a Hemisphere=3πr²;

Volume of a Hemisphere=2/3 πr³;