Bredhurst Receiving and Transmitting Society

Advanced Radio Amateur Examination

maths ...So what is next ...


So is that everything ?

Eh! well no we have still to consider 1/n which means 1 divided by any number and pi -

"reciprocal"

1/n means in mathematical terms the reciprocal. When you have easy numbers like 1/2 1/100 it is easy to use a simple calculator but in the maths you will come across in the advanced course there will be times when it would be nice to have the key on the calculator to do it for you by keying in the number and pressing a single key.

So like the for square root you will need to see a key like x-1 for the reciprocal.


"pi"

pi pronounced pie and has nothing to do with eating but is what is called a "constant term" (as whilst other number might change it does not) and it will appear in many maths calculations for the course.

Mathematically pi or is the ratio of the circumference and diameter of a circle and in simple terms is considered as 22/7 but that is a long number ( try it on your calculator) and for short we use 3.14


A complicated manipulation coming up !! Let's say you wish to find what L is equal to then we need to do some manipulation of the formula.

Manipulating FIRST multiple both sides by Square root LC

NEXT cancel out the square root LC as shown below

you are now left with this, so now divide both sides by f

so this is the result

and cancel out the f's, then to get rid of the square root we need to square all through

square root time square root just gives the root in this case LC as shown below

now divide both sides by C and the result is shown below

now cancel the C's as shown below

This can be further simplified to what is below

so that is not as difficult as you might have imagined !!


"Math's Rule" The use of brackets when using + - and X and /

There is a "Math's Rule" which says that you:

Do multiplication and division first UNLESS there are brackets when you do everything in brackets first - and if within the brackets there is multiple or divide then you do that first before the plus or minus and then proceed outside the brackets etc etc.

Thus 4 x 3 + 10 = 22 and not 52

To have the answer as 52 we would have needed this 4 x (3 + 10) which mathematically would have been written as 4(3 + 10) as the 4 prior to the bracket means multiply 4 by what is inside the brackets after you have done that part of the calculation.

Similarly 4 x 10 - 3 = 37 and not 28

but 4(10 - 3) = 28

Note: When using brackets a number before a bracket means multiply it by what is in the brackets unless there is another function shown. This is further explained below.

also when you have opened a set of brackets you must also close them, see the example below where you work out the inner most brackets first then the next set and so on.

Try to work out the answer to this 5(4(45-35)) Answer 2


Algebraic multiplication

In algebra if we have two variables say C and R for instance and we to multiple these variables together rather than putting C x R which is correct we can put CR - writing the letters together means multiply them together.

This convention is used on this page click here and here

The same would be when using brackets

A(C-D) means from C take D and multiply the result by A


and now for prefixes

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