class 9 worksheets -cbse

CBSE Worksheets for Class 9 | Download 9th Grade Worksheets for All Subjects. 9th class is very important from the board’s point of view. Because without scoring in 9th you cannot appear for the 10th standard board exams. You will have a lot of basics to learn in class 9 for further studies.

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Algebraic formulae

(a + b)2 = a2 + b2 + 2ab
(a - b)2 = a2 + b2 - 2ab
(a + b)3 = a3 + b3 +3a2b + 3ab2 or a3 + b3+-3ab (a + b)
(a - b)3 = a3 - b3 -3a2b + 3ab2 or a3 - b3 -3ab (a – b)
(a - b)2 = (a + b)2 = 2a2 + 2b2
(a + b)2 = (a - b)2 = 4ab
If a+b+c =0 then a3 + b3+ c3 = 3abc
(a+b) (a-b) = a2 - b2
(a +b +c)2 = a2 + b2+ c2 +2ab +2bc +2ca
a3 + b3+ c3 -3abc = (a +b +c) (a2 + b2+ c2 -ab-bc-ca)
(x + a) ( x + b) = x2 + ( a + b)x +ab
a2 + b2 = (a + b)2 – 2ab or a2 + b2 = (a - b)2 + 2ab
a3 – b 3 = (a - b) (a2 + ab + b2)
a3 + b 3 = (a + b) (a2 - ab + b2)