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!Ignotum/Formulae/Diff

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# Maths > Differentiation
sinx>cosx
'>' means 'goes to' rather than 'greater
than'.



cosx>-sinx





tanx>sec�x





secx>secxtanx





cosecx>-cosecxcotx





cotx>-cosec�x





e^x>e^x
Where e is the constant 2.718. This does
not change when differentiated. However,
e^ax>ae^ax.


arcsinx>1/(1-x�)^�
Arcsine=inverse sine, also written as
sin^(-1)x. This is not the same as 1/sinx
which would be written as (sinx)^-1.


arccosx>-1/(1-x�)^�
Arccosine=inverse cosine, also written as
cos^(-1)x. This is not the same as 1/cosx
which would be written as (cosx)^-1.


arctanx>1/(1+x�)
Arctan=inverse tan, also written as
tan^(-1)x. This is not the same as 1/tanx
which would be written as (tanx)^-1.


logx>1/x





(ax^b+c)^d>d(abx^(b-1))(ax^b+c)^(d-1)
To differentiate a bracket such as this
with respect to x, you would bring down
the power (d), differentiate what is in 
the bracket and multiply these by the 
bracket with the power reduced by 1.
dy/dx=(dy/du)(du/dx)
Where dy/dx is the differential of the
equation y=f(x). This is called the chain
rule and it is not as obvious as it first
seems as they are NOT fractions, but they
can sometimes be treated as if they are.
uv>v(du/dx)+u(dv/dx)
This is called the product rule, where u
and v are both functions of x.



u/v>(v(du/dx)-u(dv/dx))/v�
This is called the quotient rule where u
and v are both functions of x.






























































00000000  23 20 4d 61 74 68 73 20  3e 20 44 69 66 66 65 72  |# Maths > Differ|
00000010  65 6e 74 69 61 74 69 6f  6e 0a 73 69 6e 78 3e 63  |entiation.sinx>c|
00000020  6f 73 78 0a 27 3e 27 20  6d 65 61 6e 73 20 27 67  |osx.'>' means 'g|
00000030  6f 65 73 20 74 6f 27 20  72 61 74 68 65 72 20 74  |oes to' rather t|
00000040  68 61 6e 20 27 67 72 65  61 74 65 72 0a 74 68 61  |han 'greater.tha|
00000050  6e 27 2e 0a 0a 0a 0a 63  6f 73 78 3e 2d 73 69 6e  |n'.....cosx>-sin|
00000060  78 0a 0a 0a 0a 0a 0a 74  61 6e 78 3e 73 65 63 b2  |x......tanx>sec.|
00000070  78 0a 0a 0a 0a 0a 0a 73  65 63 78 3e 73 65 63 78  |x......secx>secx|
00000080  74 61 6e 78 0a 0a 0a 0a  0a 0a 63 6f 73 65 63 78  |tanx......cosecx|
00000090  3e 2d 63 6f 73 65 63 78  63 6f 74 78 0a 0a 0a 0a  |>-cosecxcotx....|
000000a0  0a 0a 63 6f 74 78 3e 2d  63 6f 73 65 63 b2 78 0a  |..cotx>-cosec.x.|
000000b0  0a 0a 0a 0a 0a 65 5e 78  3e 65 5e 78 0a 57 68 65  |.....e^x>e^x.Whe|
000000c0  72 65 20 65 20 69 73 20  74 68 65 20 63 6f 6e 73  |re e is the cons|
000000d0  74 61 6e 74 20 32 2e 37  31 38 2e 20 54 68 69 73  |tant 2.718. This|
000000e0  20 64 6f 65 73 0a 6e 6f  74 20 63 68 61 6e 67 65  | does.not change|
000000f0  20 77 68 65 6e 20 64 69  66 66 65 72 65 6e 74 69  | when differenti|
00000100  61 74 65 64 2e 20 48 6f  77 65 76 65 72 2c 0a 65  |ated. However,.e|
00000110  5e 61 78 3e 61 65 5e 61  78 2e 0a 0a 0a 61 72 63  |^ax>ae^ax....arc|
00000120  73 69 6e 78 3e 31 2f 28  31 2d 78 b2 29 5e bd 0a  |sinx>1/(1-x.)^..|
00000130  41 72 63 73 69 6e 65 3d  69 6e 76 65 72 73 65 20  |Arcsine=inverse |
00000140  73 69 6e 65 2c 20 61 6c  73 6f 20 77 72 69 74 74  |sine, also writt|
00000150  65 6e 20 61 73 0a 73 69  6e 5e 28 2d 31 29 78 2e  |en as.sin^(-1)x.|
00000160  20 54 68 69 73 20 69 73  20 6e 6f 74 20 74 68 65  | This is not the|
00000170  20 73 61 6d 65 20 61 73  20 31 2f 73 69 6e 78 0a  | same as 1/sinx.|
00000180  77 68 69 63 68 20 77 6f  75 6c 64 20 62 65 20 77  |which would be w|
00000190  72 69 74 74 65 6e 20 61  73 20 28 73 69 6e 78 29  |ritten as (sinx)|
000001a0  5e 2d 31 2e 0a 0a 0a 61  72 63 63 6f 73 78 3e 2d  |^-1....arccosx>-|
000001b0  31 2f 28 31 2d 78 b2 29  5e bd 0a 41 72 63 63 6f  |1/(1-x.)^..Arcco|
000001c0  73 69 6e 65 3d 69 6e 76  65 72 73 65 20 63 6f 73  |sine=inverse cos|
000001d0  69 6e 65 2c 20 61 6c 73  6f 20 77 72 69 74 74 65  |ine, also writte|
000001e0  6e 20 61 73 0a 63 6f 73  5e 28 2d 31 29 78 2e 20  |n as.cos^(-1)x. |
000001f0  54 68 69 73 20 69 73 20  6e 6f 74 20 74 68 65 20  |This is not the |
00000200  73 61 6d 65 20 61 73 20  31 2f 63 6f 73 78 0a 77  |same as 1/cosx.w|
00000210  68 69 63 68 20 77 6f 75  6c 64 20 62 65 20 77 72  |hich would be wr|
00000220  69 74 74 65 6e 20 61 73  20 28 63 6f 73 78 29 5e  |itten as (cosx)^|
00000230  2d 31 2e 0a 0a 0a 61 72  63 74 61 6e 78 3e 31 2f  |-1....arctanx>1/|
00000240  28 31 2b 78 b2 29 0a 41  72 63 74 61 6e 3d 69 6e  |(1+x.).Arctan=in|
00000250  76 65 72 73 65 20 74 61  6e 2c 20 61 6c 73 6f 20  |verse tan, also |
00000260  77 72 69 74 74 65 6e 20  61 73 0a 74 61 6e 5e 28  |written as.tan^(|
00000270  2d 31 29 78 2e 20 54 68  69 73 20 69 73 20 6e 6f  |-1)x. This is no|
00000280  74 20 74 68 65 20 73 61  6d 65 20 61 73 20 31 2f  |t the same as 1/|
00000290  74 61 6e 78 0a 77 68 69  63 68 20 77 6f 75 6c 64  |tanx.which would|
000002a0  20 62 65 20 77 72 69 74  74 65 6e 20 61 73 20 28  | be written as (|
000002b0  74 61 6e 78 29 5e 2d 31  2e 0a 0a 0a 6c 6f 67 78  |tanx)^-1....logx|
000002c0  3e 31 2f 78 0a 0a 0a 0a  0a 0a 28 61 78 5e 62 2b  |>1/x......(ax^b+|
000002d0  63 29 5e 64 3e 64 28 61  62 78 5e 28 62 2d 31 29  |c)^d>d(abx^(b-1)|
000002e0  29 28 61 78 5e 62 2b 63  29 5e 28 64 2d 31 29 0a  |)(ax^b+c)^(d-1).|
000002f0  54 6f 20 64 69 66 66 65  72 65 6e 74 69 61 74 65  |To differentiate|
00000300  20 61 20 62 72 61 63 6b  65 74 20 73 75 63 68 20  | a bracket such |
00000310  61 73 20 74 68 69 73 0a  77 69 74 68 20 72 65 73  |as this.with res|
00000320  70 65 63 74 20 74 6f 20  78 2c 20 79 6f 75 20 77  |pect to x, you w|
00000330  6f 75 6c 64 20 62 72 69  6e 67 20 64 6f 77 6e 0a  |ould bring down.|
00000340  74 68 65 20 70 6f 77 65  72 20 28 64 29 2c 20 64  |the power (d), d|
00000350  69 66 66 65 72 65 6e 74  69 61 74 65 20 77 68 61  |ifferentiate wha|
00000360  74 20 69 73 20 69 6e 20  0a 74 68 65 20 62 72 61  |t is in .the bra|
00000370  63 6b 65 74 20 61 6e 64  20 6d 75 6c 74 69 70 6c  |cket and multipl|
00000380  79 20 74 68 65 73 65 20  62 79 20 74 68 65 20 0a  |y these by the .|
00000390  62 72 61 63 6b 65 74 20  77 69 74 68 20 74 68 65  |bracket with the|
000003a0  20 70 6f 77 65 72 20 72  65 64 75 63 65 64 20 62  | power reduced b|
000003b0  79 20 31 2e 0a 64 79 2f  64 78 3d 28 64 79 2f 64  |y 1..dy/dx=(dy/d|
000003c0  75 29 28 64 75 2f 64 78  29 0a 57 68 65 72 65 20  |u)(du/dx).Where |
000003d0  64 79 2f 64 78 20 69 73  20 74 68 65 20 64 69 66  |dy/dx is the dif|
000003e0  66 65 72 65 6e 74 69 61  6c 20 6f 66 20 74 68 65  |ferential of the|
000003f0  0a 65 71 75 61 74 69 6f  6e 20 79 3d 66 28 78 29  |.equation y=f(x)|
00000400  2e 20 54 68 69 73 20 69  73 20 63 61 6c 6c 65 64  |. This is called|
00000410  20 74 68 65 20 63 68 61  69 6e 0a 72 75 6c 65 20  | the chain.rule |
00000420  61 6e 64 20 69 74 20 69  73 20 6e 6f 74 20 61 73  |and it is not as|
00000430  20 6f 62 76 69 6f 75 73  20 61 73 20 69 74 20 66  | obvious as it f|
00000440  69 72 73 74 0a 73 65 65  6d 73 20 61 73 20 74 68  |irst.seems as th|
00000450  65 79 20 61 72 65 20 4e  4f 54 20 66 72 61 63 74  |ey are NOT fract|
00000460  69 6f 6e 73 2c 20 62 75  74 20 74 68 65 79 0a 63  |ions, but they.c|
00000470  61 6e 20 73 6f 6d 65 74  69 6d 65 73 20 62 65 20  |an sometimes be |
00000480  74 72 65 61 74 65 64 20  61 73 20 69 66 20 74 68  |treated as if th|
00000490  65 79 20 61 72 65 2e 0a  75 76 3e 76 28 64 75 2f  |ey are..uv>v(du/|
000004a0  64 78 29 2b 75 28 64 76  2f 64 78 29 0a 54 68 69  |dx)+u(dv/dx).Thi|
000004b0  73 20 69 73 20 63 61 6c  6c 65 64 20 74 68 65 20  |s is called the |
000004c0  70 72 6f 64 75 63 74 20  72 75 6c 65 2c 20 77 68  |product rule, wh|
000004d0  65 72 65 20 75 0a 61 6e  64 20 76 20 61 72 65 20  |ere u.and v are |
000004e0  62 6f 74 68 20 66 75 6e  63 74 69 6f 6e 73 20 6f  |both functions o|
000004f0  66 20 78 2e 0a 0a 0a 0a  75 2f 76 3e 28 76 28 64  |f x.....u/v>(v(d|
00000500  75 2f 64 78 29 2d 75 28  64 76 2f 64 78 29 29 2f  |u/dx)-u(dv/dx))/|
00000510  76 b2 0a 54 68 69 73 20  69 73 20 63 61 6c 6c 65  |v..This is calle|
00000520  64 20 74 68 65 20 71 75  6f 74 69 65 6e 74 20 72  |d the quotient r|
00000530  75 6c 65 20 77 68 65 72  65 20 75 0a 61 6e 64 20  |ule where u.and |
00000540  76 20 61 72 65 20 62 6f  74 68 20 66 75 6e 63 74  |v are both funct|
00000550  69 6f 6e 73 20 6f 66 20  78 2e 0a 0a 0a 0a 0a 0a  |ions of x.......|
00000560  0a 0a 0a 0a 0a 0a 0a 0a  0a 0a 0a 0a 0a 0a 0a 0a  |................|
*
00000590  0a 0a 0a 0a 0a 0a 0a 0a  0a                       |.........|
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