Small difference between mathematic operator and sign

            Most of the students could not find the deference between mathematical operator like subtraction, addition, multiplication and division and sign +ve and –ve and fails in competitive mathematics with mistake. To avoid the mistake, please read the following examples.

Find out operator and sign

E.g 1:   2+3=5 in this equation + is operator i.e addition and the sign of two numbers is +ve [the numbers without sign means +ve numbers] simply addition of two +ve numbers.

E.g2:    7-3=4 here – is an  operator of subtraction and the two numbers 7 and 3 are +ve

            The same can be written as 7+[-3] here operator is + i.e addition but sign of the 3 is –ve i.e addition of one +ve number 7 and one –ve number -3.

E.g3:    8-[-3]=11 here operator is 1^{st “} –“ and sign of 8 is +ve and sign of 3 is –ve

E.g4:    -8/[-16]=1/2 here operator of the two numbers is / sign of the numbers is –ve.

Finding of unknown number ‘X’

E.g1:    if X/[-2]=8 then the X=8x[-2] the sign of the denominator cannot be changed from RHS to LHS to find out value of the X only operator  / can be changed i.e the number -2 is dividing X on LHS and to find  X valve the -2 multiply 8 one RHS without changing of it’s sign.

E.g2:    if X-2=8, then X=8+2 here 2is subtracted from X on LHS and to find out X, 2 is to be added on RHT without changing it’s sign +ve. [as X-[+2]=8].

E.g 3:   If Xx[-2]=8 then X=8/ -2  here -2 is multiplying the X on LHS and to find out the X the number -2 is dividing the 8 on RHS without changing it,s sign –ve.

E.g4:    If X/[-2]=8 then X=8x[ -2]  here -2 is dividing the X on LHS and to find out the X the number -2 is multiply the 8 on RHS without changing its sign –ve.

Conclusion:

The operator is different from sign. The operation between two numbers changes from LHS to RHS while finding out of unknown values, without changing its sign of the number other than the number to be findout on LHS.

[Note : Aim of the blog is to make the students bright in mathematics and make the parents as teachers.]

Addition of the numbers

Addition of the two +ve numbers gives a +ve number.

+ve number+ +ve number=+ve number

e.g : 3+5=7

Addition of the two –ve numbers gives a –ve number

-ve number+ -ve number=-ve number

-7+[-3]=-10

Addition of one –ve number and one +ve number vice versa gives the difference between the numbers with the bigger numbers sign.

-ve number+ +ve number= Sign of big number [difference of the numbers]

e.g: -3+2=-1 here the sign of the big number is –ve and difference between the numbers 3 and 2 is 1.

e.g: -7+10=3 here the sign of the big number is +ve and difference between the numbers 10 and 7 is 3.  

Conclusion

*Addition of the similar sign numbers gives the some of the numbers with same  sign.

*Addition of the different sing numbers give the difference of the numbers with bigger number sign.

Multiplication

Multiplication or division between two +ve numbers give a +ve number

e.g: 3x5=15

Multiplication or division of between two –ve numbers gives +ve number

E.g: -3x[-5]=15

Multiplication or division between one –ve number and one +ve number vice versa gives –ve number.

E.g: -3x5=-15

E.g: -15/3=-5

E.g: 3x[-5]=-15

E.g: 15/[-5]=-3

 Conclusion

*Multiplication or division between the similar sign numbers gives always +ve number.

*Multiplication or division between the different sign numbers gives always –ve number.