All mathematics formulae from chapter 1 to 5 for CBSE class 10th

 

                 -:Real numbers:-

Euclid's Division Lemma:- 

It's state that, for any two positive (let a and b), there exist two unique integers (let q and r), such that 

a= bq + r, where 0≤r<b.
Here, a= Dividend ,b= Divisor , 
q= Quotient and r= Remainder

                         -:Polynomials:-

Relationship between zeroes & coefficients of a Polynomial:

 Let α and β be the zeroes of the quadratic polynomial p(x)= ax²+bx+c, a≠0, then (x-α) and (x-β) both are factors of p(x).

Therefore, ax² + bx +c = k (x-α) (x-β)

                                     = k[x² -(α+β)x+αβ]

Where,k is some constant.

  

On comparing the coefficients of x²,x and constant term from both sides, we get a=k, b=-k(α+β)

and c=kαβ

For a Cubic Polynomial

Formation of quadratic and cubic polynomial

• If α and β are the zeroes of quadratic polynomial then quadratic polynomial=x²-(sum of zeroes)x+ product of zeroes,i.e. x²-(α+β)x+αβ
• If α,β and γ are the zeroes of the cubic polynomial, then cubic polynomial= x³-(sum of zeroes)x²+(sum of the product of zeroes taking two at a time)x-product of zeroes   i.e.x³-(α+β+γ)x²+(αβ+βγ+γα)x-αβγ

 -:Pair of Linear equation in two variable:-

Algebraic Methods for Solving a pair of Linear Equations:-

Some of the algebraic methods for solving a pair of linear equations are:

1. Substitution method

2. Elimination method

3. Cross-Multiplication method

Substitution method

In this method, valu of one variable can be found out in the terms of other variable from one of the given equation and this value is substituted in other equation, then we get an equation in one variable, which can be solved easily. For example:-

Ques-

Sol-

Elimination method

In this method, one variable out of the two variable equal in both the equations.

After eliminating that variable, the left equation is an equation in one variable, which can be solved easily. For example:

Ques-

 Sol-

Cross-Multiplication Method

Formula=

Remembering technique:-

         -: Quadratic Equations:-

Quadratic formula:

This is also called as Shridharacharya's rule.

Nature of the roots of a quadratic equation

          - :Arithmetic Progression:-

To Find the general term of an AP

The nth term of an AP is called its general term.

To Find the nth term from the end of an AP

Arithmetic Mean
Arithmetic Mean between a and b is ½(a+b)

To Find Sum of n terms of an AP