Commander Faie wrote:danchia wrote:Commander Faie wrote:sorry ah...study too much forgot the term "battle damage"...lol
Poor thing .... make sure your brain is not "overstudy damaged" by the end of this year, my friend.
So siao lor, dunno what terms like ' 2,4-dinitrophenylhydrazine' la, then got what fern la then what moss la...omg! then the maths complex no. dunno learn for what. in real life i dun count sq root of negative nos. HAHHAHA
Hmmm .... 2,4-dinitrophenylhydrazine - you mean Brady's Reagent , the highly flammable red powder that is stable when wet, but explosive when dry, usually shock sensitive when dry and incompatible with strong oxidizing agents ?
Dunno .... never heard of it.
Oh and don't get me started about Ferns and Mosses . Did you know that if you look underneath a fern frond, you will often see small clumps, spots or patches that look like they are stuck onto the under surface of the pinnae. These patches are where you find the spores. The spores grow inside casings called sporangia. The sporangia may clump together into what are called sori (singular: sorus) . Great ! Who cares ?
Oh and did you know that the moss sporophyte is typically a capsule growing on the end of a stalk called the seta. The sporophyte contains no clorophyl of its own: it grows parasitically on its gametophyte mother. As the sporophyte dries out, the capsule release spores which will grow into a new generation of gametophytes, if they germinate.
Well , neither did I .
But Maths Complex Numbers is easy, Commander Faie .... don't be afraid of it. It's quite easy to understand . Never fear..... I teach you .... Are you ready? OK, here goes :
Complex numbers are a fascinating extension to "normal" maths. They
are used a great deal at the university level.
I'm not certain of the history of the discovery of complex numbers,
but I know that someone thought of them at least as early as the
sixteenth century, although they suggested them more as a joke than as
"serious" maths.
The easiest way to describe complex numbers is that they are a way of
finding the square root of a negative number. You have probably been
told at some time that this is not possible and with normal numbers,
it isn't. But if we invent a new kind of number, called complex
numbers (or imaginary numbers), it is.
We start by calling the square root of -1 by the letter i (some people
use j). We then say that the square root of any negative number is
the square root of the positive number multiplied by i. So the square
root of -16 is 4i.
The second aspect of complex numbers comes from trying to answer the
question "what happens if we add a real number to a complex number?"
(a real number is the kind of number you are used to using).
The way of understanding this kind of question is generally described
with a special diagram called an Argand diagram.
Imagine drawing the number line across your page like the x axis of a
graph. Any real number can be represented as a point on this line, so
we call it the "real axis". But i and the other complex numbers do
not fit in between the real numbers; they are completely different
things. So we draw another axis upwards, called the "imaginary axis",
like this:
^Im
|
1-
|
|
---|----+----|----|-->Re
-1 | 1 2
|
-1- x
|
Any number on the imaginary axis represents that number times i.
So where I have put 1 on the imaginary axis, it means i.
Now, if we try to add a real number and a complex number, the answer
doesn't fit on either axis, because it has a real part and a complex
part which won't go together. So we mark a point on the diagram which
corresponds to the answer by measuring the real part along the real
axis and the imaginary part on the imaginary axis.
So the place where I have put a "x" on the diagram represents the
complex number 2 + (-1)*i, which is normally just written 2-i.
I'm going to stop there, but there is a LOT more things which complex
numbers do. In answer to your question about what kind of problems
they solve, the simplest answer is - complex ones! They are used in
engineering and in the design of computers but mainly they are used by
mathematicians when they are working on other more complicated
theorems.
I don't know if you have studied quadratic equations, but complex
numbers provide the answers to some of these which would have been
impossibe to solve before. For example, the solutions to the
quadratic equation x^2-6x+25=0 are 3+4i and 3-4i. You can show that
they work by putting them into the equation:
(3+4i)^2-6(3+4i)+25 = (9+24i+16i^2)-(18+24i)+25
= 9+24i+16i^2-18-24i+25
= 16+16i^2
but i is the square root of (-1), so i^2 = -1, so
= 16-16
= 0
You can try it yourself with (3-4i) and you should get the same
answer.
See , easy right ? No sweat man !!!
LOL