Some Useful Algebra Formulas
Algebra Formulas are very important for mathematics as well as science. If you are an aspirant of competitive exams like SSC, CGL, Rail NTPC, Police, Defence, etc. then you should remember all the formulas. Remembering formula is not going to help to crack any examinations, one should have the ability to execute these formulas in the exam hall. To do so one has to practice the various types of algebraic math problems.
Contents Square Formula Cube Formula Laws of Exponent Quadratic Formula Irrational number Formula
Some Important Formulas of Algebra
Square Formula
(x+y)2 = (x+y)(x+y) = x2+2xy+y2
(x-y)2 = (x-y)(x-y) = x2-2xy+y2
(x+y)2 = (x-y)2 + 4xy
(x-y)2 = (x+y)2 – 4xy
x2-y2 = (x+y)(x+y)
(x + y + z)2 = x2 + y2 + z2 + 2xy + 2xz + 2yx
4xy = [ (x+y)2 – (x-y)2 ]
2( x2+y2) = [ (x+y)2 + (x-y)2 ]
Cube Formula
(x + y)3 = x3 + 3x2y + 3xy2 + y3
(x + y)3 = x3 + y3 + 3xy(x + y)
(x – y)3 = x3 – 3x2y + 3xy2 – y3
(x – y)3 = x3 – y3 – 3xy(x – y)
x3 + y3 = (x + y)(y2 – xy + y2)
x3 – y3 = (x – y)(x2 + xy + y2)
(x + y)4 = x4 + 4x3y + 6x2y2 + 4xy3 + y4)
(x – y)4 = x4 – 4x3y + 6x2y2 – 4xy3 + y4)
x4 – y4 = (x2 + y2)(x + y) (x – y)
x3 + y3 + z3 – 3xyz = (x + y + z)( x2 + y2 + z2 -xy – yz – zx)
Laws of Exponent
xm × xn = xm+n
xm / xn = xm-n
(xy)m = xm × ym
(xm)n = xmn
xm = (1/x-m)
x0 = 1
√x = x½
³√x = x¹/³
‘Quadratic Formula :
If a Quadratic Equation is ax2 + bx + c = 0 ; Then the roots of this equation are –
The formula of Irrational number
