# What is the difference ?

called The difference of the result obtained by subtracting the smaller number from the larger.In this case, the first number is subtracted from the other, is named decreases (because that is what we are reducing in the process).The second is subtracted from the first day, and is called deductible.In sum, with the difference is subtracted is reduced, and the difference between the reduced and the difference becomes deductible.In cases where the subtrahend is greater than a decrease, the difference becomes negative numbers.

There are several difference formulas:

- formula difference ab = a
- formula of the squares of the difference a2 - b2 = (a - b) * (a + b)
- formula cubes difference a3 - b3 = (a - b) *(a2 + ab + b2)
- formula difference formula square potentials U = Aq
- difference (a - b) 2 = a2 - 2ab + b2
- cube formula of the difference (a - b) 3 = a3 - 3a2b + 3ab2 -b3

## What is the difference and how to find

Calculate the difference, you can use the usual, familiar to us calculator.To do this, press the button "C" to enter the number is decreased, then press the "-" button and enter the subtrahend.The result obtain by pressing the "=" key.There are also less common model calculators feedback, so-called Polish notation.Here, to calculate the difference, instead of the "-" button, press the up arrow (due to this, the number of switches in the stack or memory card action).After that, enter subtracted and press the button "-" to give a ready answer.

There is also a summing device, the possibility of which includes only the addition of numbers.It is possible to find a difference and using it.For this purpose, it is necessary to reduce the mentally subtracted by 1. After that, the numbers translate into the category of additional, where 0 is equal to 9, 1 is equal to 8, etc.Senior level, remaining free, fill nines.Folded components of this kind of difference makes the device counter overflow and indicate the difference.

## What is the potential difference

potential difference concept used by physicists.Get the potential difference can be by connecting a voltmeter to the two points of the circuit where the voltage is equal to the first conditional U1, and the second - U2.In this case, the voltmeter will show the result in the form of voltage U1-U2, which is called the potential difference.Any electrochemical cell produces a voltage which determines the difference of electrochemical potentials substances constituting element electrodes.

Before invented voltage regulators, to calibrate voltmeters allowed elements Weston.reactive components are selected in them provide a high level of stability of the potential difference.There is also the concept of differential pressure, used in hydraulic and pneumatic weapon.This difference is analogous to the difference between the electrical potentials.

## How to teach your child addition and subtraction

Even before the school the child is recommended to master basic math, get the concept of what is the difference or the sum.To make it easier for the baby to consider, use in learning any means available.Do not be afraid to visualize the problem.For example, your child will be much easier to decide how many apples he will, if he will share half with a friend on the real things, not the faceless piece of paper.

very popular with children and problems associated with guessing.For example.Referential Example "2 + 2 = 4" can be replaced with "x + 2 = 4".This exercise will force the child to think not from a template and develop logic.