# Common Algebra Formulae

Posted in Algebra | Email This Post |Following are the most commonly and widely used algebra equations.

1) (a+b)^{2}=a^{2}+b^{2}+2ab

2) (a-b)^{2}=a^{2}+b^{2}-2ab

3) (a+b+c)^{2}=a^{2}+b^{2}+c^{2}+2ab+2bc+2ca

4) (a+b)(a-b)= a^{2}-b^{2}

5) (a+b)^{3}= a^{3}+b^{3}+3ab(a+b)

6) (a-b)^{3}= a^{3}-b^{3}-3ab(a-b)

7) (a+b)^{2}-(a-b)^{2}=4ab

8 ) (a+b)^{2}+(a-b)^{2}=2(a^{2}+b^{2})