Basic Formula of Algebra
1.    (a + b)2 = a2 +
2ab + b2
2.    (a - b)2 = a2 -
2ab + b2
3.    a2 + b2 = (a +
b)2 – 2ab
4.    a2 + b2 = (a -
b)2 + 2ab
5.    (a + b)2 = (a – b)2
+ 4ab
9. (a + b+ c)2 = a2 + b2 + c2 + 2ab + 2bc + 2ca
10.   a2 + b2 + c2 =
(a + b + c)2 – 2(ab + bc + ca)
11.   2(ab + bc + ca) = (a + b + c)2 – (a2
+ b2 + c2)
12.   (a + b) (a – b) = a2 – b2 
13.   (x + a) (x + b) = x2 + (a + b)x +
ab
14.   (x + a) (x – b) = x2 + (a – b)x –
ab
15.   (x – a) (x + b) = x2 + (a – b)x –
ab
16.   (x – a) (x – b) = x2 – (a + b)x +
ab
17.   (a + b)3 = a3 + 3a2b
+ 3ab2 + b3 
18.   (a – b)3 = a3 – 3a2b
+ 3ab2 – b3 
19.   a3 + b3 = (a+ b)3
– 3ab (a + b)
20.   a3 – b3 = (a – b)3
+ 3ab (a – b)
21.   (a + b) (a2 – ab + b2) =
a3 + b3
22.  (a – b) (a2 + ab + b2)
= a3 – b3
23.  (x + a) (x + b) (x + c) = x3
+ (a + b + c)x2 + (bc + ca + ab)x + abc
24.  (x – a) (x – b) (x – c) = x3
– (a + b + c)x2 + (bc + ca + ab)x – abc

No comments:
Post a Comment
Please comments for this site.