Nawaachia Homework wale wa mambo yetu yaleee back in days (still got it?).....!!!!!

Nawaachia Homework wale wa mambo yetu yaleee back in days (still got it?).....!!!!!

Zzzzzz! Mi ni mtaalam wa 2+2=4 mambo ya let x = y, given x + y=3,nawaachia manguli.
 
Ukisoma Engineering hasa Electrical ndio utajua zinakua applied vipi hasa kwenye Magnetic kama ilivyo Complex na Matrices kwenye Power System. Ndio maana Engineers hasa wa umeme wanajua sana hesabu.
 
Differential equations zinatumika sana kwenye modelling, huo mziki wa modelling usikie tu, ninaweza kuufananisha na turbo machinery au energy n materials balance
 

<!--[if !mso]> <style> v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} </style> <![endif]-->Qn1 (1+y[SUP]2[/SUP])dx-[y-(1+y)[SUP]1/2[/SUP]](1+x)[SUP]3/2[/SUP]dy

Rearanging the above equations, colleting similar variables together (separating thevariables) and thereafter simplifying, gives the following expressions


(1+x)-[SUP]3/2[/SUP]dx=[y-(1+y)[SUP]1/2[/SUP]]/(1+y[SUP]2[/SUP])dy


&#10233;(1+x)-[SUP]3/2[/SUP]dx=[y/(1+y[SUP]2[/SUP])]dy&#8211;[(1+y)[SUP]1/2[/SUP]/(1+y[SUP]2[/SUP])] dy


The LHS integrates to


-2(1+x)-[SUP]1/2[/SUP]
.............................................................(1) whereas;


the first term [y/(1+y[SUP]2[/SUP])]dyon the RHS integrates to

[SUP]
1[/SUP]/[SUB]2[/SUB]ln(1+y[SUP]2[/SUP])................................................................(2)


Now it remains to find theintegral of [(1+y)[SUP]1/2[/SUP]/(1+y[SUP]2[/SUP])] dy.


Let I=&#10780;[(1+y)[SUP]1/2[/SUP]/(1+y[SUP]2[/SUP])]dy.............................(3)

Again, if we let u=(1+y)[SUP]1/2[/SUP]


Then u[SUP]2[/SUP]=1+y


&#10233;2udu=dy


Therefore I=
&#10780;[(1+y)[SUP]1/2[/SUP]/(1+y[SUP]2[/SUP])]dy=&#10780;[2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2)]du.


Therefore, the change ofvariable from y to u transforms the integral to


I=
&#10780;[2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2)]du,


which can be split intopartial fractions whose denominators must be the roots of the polynomialequation u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2=0




Solving for the roots of the polynomial u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2


By considering the polynomialu[SUP]4[/SUP]-2u[SUP]2[/SUP]+2 as a quadratic equation in u[SUP]2[/SUP] i.e. u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2=(u[SUP]2[/SUP])[SUP]2[/SUP]-2(u[SUP]2[/SUP])+2,then we can solve for u[SUP]2 [/SUP]in the quadratic equation (u[SUP]2[/SUP])[SUP]
2[/SUP]-2(u[SUP]2[/SUP])+2=0


Therefore u[SUP]2[/SUP]
<v:shapetype id="_x0000_t75" stroked="f" filled="f" path="m@4@5l@4@11@9@11@9@5xe" o😛referrelative="t" o:spt="75" coordsize="21600,21600"> <v:stroke joinstyle="miter"> <v:f eqn="if lineDrawn pixelLineWidth 0"> <v:f eqn="sum @0 1 0"> <v:f eqn="sum 0 0 @1"> <v:f eqn="prod @2 1 2"> <v:f eqn="prod @3 21600 pixelWidth"> <v:f eqn="prod @3 21600 pixelHeight"> <v:f eqn="sum @0 0 1"> <v:f eqn="prod @6 1 2"> <v:f eqn="prod @7 21600 pixelWidth"> <v:f eqn="sum @8 21600 0"> <v:f eqn="prod @7 21600 pixelHeight"> <v:f eqn="sum @10 21600 0"> </v:f> <v😛ath o:connecttype="rect" gradientshapeok="t" o:extrusionok="f"> <o:lock aspectratio="t" v:ext="edit"></o:lock><v:shape id="_x0000_i1025" style="width: 90pt; height: 34.5pt;" type="#_x0000_t75"> <v:imagedata o:title="" chromakey="white" src="file:///C:\Users\machibya\AppData\Local\Temp\msohtmlclip1\01\clip_image001.png"></v:imagedata></v:shape></v😛ath></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:stroke></v:shapetype> where <v:shape id="_x0000_i1025" style="width: 39pt; height: 21.75pt;" type="#_x0000_t75"> <v:imagedata o:title="" chromakey="white" src="file:///C:\Users\machibya\AppData\Local\Temp\msohtmlclip1\01\clip_image002.png"></v:imagedata></v:shape> , b=-2 and c=+2 which gives two conjugatecomplex roots:


u[SUP]2[/SUP]
=1+i or


u[SUP]2[/SUP]
=1-i


Therefore 2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2can be written in the partial fractions form as


A/[u[SUP]2[/SUP]-(1+i)]+B/[u[SUP]2[/SUP]-(1-i)]=2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2) where A and B are coefficientswhich need to be detemined. On solving however, we get


A=1-i and


B=1+i


&#10233;2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2)can be written as


(1-i)/[u[SUP]2[/SUP]-(1+i)]+ (1+i)/[u[SUP]2[/SUP]-(1-i)]


Therefore


2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2)=(1-i)/[u[SUP]2[/SUP]-(1+i)]+ (1+i)/[u[SUP]2[/SUP]-(1-i)] and hence


I=
&#10780;[2u[SUP]2[/SUP]/(u[SUP]4[/SUP]-2u[SUP]2[/SUP]+2)]du=&#10780;{(1-i)/[u[SUP]2[/SUP]-(1+i)]+ (1+i)/[u[SUP]2[/SUP]-(1-i)]}du...................................................................................................................(4)


I=
&#10780;{(1-i)/[u[SUP]2[/SUP]-(1+i)]}du+&#10780;{(1+i)/[u[SUP]2[/SUP]-(1-i)]} du


Now let &#945;[SUP]2[/SUP]=1+i and&#946;[SUP]2[/SUP]=1-i


Therefore I=
&#10780;{(1-i)/[u[SUP]2[/SUP]-(1+i)]}du+&#10780;{(1+i)/[u[SUP]2[/SUP]-(1-i)]} du


Changes to the expressions interms of &#945; and &#946; as


I=
&#10780;[&#946;[SUP]2[/SUP]/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])]du+&#10780;[&#945;[SUP]2[/SUP]/(u[SUP]2[/SUP]-&#946;[SUP]2[/SUP])]du............................(5)


Let L=
&#10780;[&#946;[SUP]2[/SUP]/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])]du and


M=
&#10780;[&#945;[SUP]2[/SUP]/(u[SUP]2[/SUP]-&#946;[SUP]2[/SUP])]du


So that I=L+M


Now consider the first partof the integral in equation (5)


L=
&#10780;[&#946;[SUP]2[/SUP]/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])]du


Now, if we let u/&#945;=sec&#952;


&#10233;u=&#945;sec&#952; &#10233;du= &#945;sec&#952;tan&#952;d&#952;


Therefore L=
&#10780;[&#946;[SUP]2[/SUP]/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])]du=&#946;[SUP]2[/SUP]/&#945;[SUP] 2[/SUP]&#10780;&#945;sec&#952;tan&#952;d&#952;/(sec[SUP]2[/SUP]&#952;-1)


L=&#946;[SUP]2[/SUP]/&#945;[SUP] 2[/SUP]
&#10780;&#945;sec&#952;tan&#952;d&#952;/(sec[SUP]2[/SUP]&#952;-1)=&#946;[SUP]2[/SUP]/&#945;[SUP] 2[/SUP]&#10780;&#945;sec&#952;tan&#952;d&#952;/tan[SUP]2[/SUP]&#952;


&#10233;L= &#946;[SUP]2[/SUP]/&#945;
&#10780;sec&#952;d&#952;/tan&#952;


=&#946;[SUP]2[/SUP]/&#945;
&#10780;sec&#952;d&#952;/tan&#952;


=&#946;[SUP]2[/SUP]/&#945;
&#10780;cosec&#952;d&#952;=(-&#946;[SUP]2[/SUP]/&#945😉ln(cosec&#952;+cot&#952😉


However, in any right angledtriangle where sec&#952;=u/&#945; (or cos &#952;=&#945;/u), one must be able to show that


cosec&#952;=u/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])[SUP]1/2[/SUP]and cot&#952;= &#945;/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])[SUP]1/2[/SUP] .Therefore


L=(-&#946;[SUP]2[/SUP]/&#945😉ln[u/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])[SUP]1/2[/SUP]+&#945;/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])[SUP]1/2[/SUP]]


&#10233; L=(-&#946;[SUP]2[/SUP]/&#945😉ln[(u+ &#945; )/(u[SUP]2[/SUP]-&#945;[SUP]2[/SUP])[SUP]1/2[/SUP]]


L=(-&#946;[SUP]2[/SUP]/&#945😉ln{(u+&#945; )/[(u+ &#945😉[SUP]1/2[/SUP] (u-&#945😉[SUP] 1/2[/SUP]]}


L=(-&#946;[SUP]2[/SUP]/&#945😉ln[(u+&#945😉[SUP]1/2[/SUP]/(u-&#945😉[SUP]1/2[/SUP]]


L=(&#946;[SUP]2[/SUP]/2&#945😉ln[(u-&#945😉/(u+&#945😉].............................................(7)


Logically, in a similarfashion


M=(&#945;[SUP]2[/SUP]/2&#946😉ln[(u-&#946😉/(u+&#946😉].............................................(8)


Therefore


I=L+M


I=
&#10780;{(&#946;[SUP]2[/SUP]/2&#945😉ln[(u-&#945😉/(u+&#945😉}du+&#10780;{(&#945;[SUP]2[/SUP]/2&#946😉ln[(u-&#946😉/(u+&#946😉]}du


can now be written as


I=(&#946;[SUP]2[/SUP]/2&#945😉ln[(u-&#945😉/(u+ &#945😉]+ (&#945;[SUP]2[/SUP]/2&#946😉ln[(u-&#946😉/(u+&#946😉]..................................................................................................................................(9)

where


u=(1+y)[SUP]1/2[/SUP],


&#945;=[(1+i)[SUP]1/2[/SUP] ,-(1+i)[SUP]1/2[/SUP])]and


&#946;=[(1-i)[SUP]1/2[/SUP],-(1-i)[SUP]1/2[/SUP])]


Therefore relatingand/combining equations (1), (2) and (9) above gives


-2(1+x)-[SUP]1/2[/SUP]=[SUP]1[/SUP]/[SUB]2[/SUB]ln(1+y[SUP]2[/SUP])+(&#946;[SUP]2[/SUP]/2&#945😉ln[(u-&#945😉/(u+&#945😉]+ (&#945;[SUP]2[/SUP]/2&#946😉ln[(u-&#946😉/(u+&#946😉] .....................................................................................................(10).


If we put u=(1+y)[SUP]1/2[/SUP],&#945;=(1+i)[SUP]1/2[/SUP], and &#946;=(1-i)[SUP]1/2[/SUP] in equation (10) above we get

-2(1+x)-[SUP]1/2[/SUP]=[SUP]1[/SUP]/[SUB]2[/SUB]ln(1+y[SUP]2[/SUP])+[(1-i)/2(1+i)[SUP]1/2[/SUP]]ln{[(1+y)[SUP]1/2[/SUP]-(1+i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]+(1+i)[SUP]1/2[/SUP]]}+[(1+i)/2(1-i)[SUP]1/2[/SUP] ]ln{[(1+y)[SUP]1/2[/SUP]-(1-i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]+(1-i)[SUP]1/2[/SUP]]}


&#10233;f(x,y)= 2(1+x)-[SUP]1/2[/SUP]+[SUP]1[/SUP]/[SUB]2[/SUB]ln(1+y[SUP]2[/SUP])+[(1-i)/2(1+i)[SUP]1/2[/SUP]]ln{[(1+y)[SUP]1/2[/SUP]-(1+i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]+(1+i)[SUP]1/2[/SUP]]}+[(1+i)/2(1-i)[SUP]1/2[/SUP] ]ln{[(1+y)[SUP]1/2[/SUP]-(1-i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]+(1-i)[SUP]1/2[/SUP]]}=0


is one implicit solution tothe above DE in Question1


Again, if we put u=(1+y)[SUP]1/2[/SUP],&#945;=-(1+i)[SUP]1/2[/SUP], and &#946;=-(1-i)[SUP]1/2[/SUP] in equation (10) above weget


-2(1+x)-[SUP]1/2[/SUP]=[SUP]1[/SUP]/[SUB]2[/SUB]ln(1+y[SUP]2[/SUP])-[(1-i)/2(1+i)[SUP]1/2[/SUP]]ln{[(1+y)[SUP]1/2[/SUP]+(1+i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]-(1+i)[SUP]1/2[/SUP]]}-[(1+i)/2(1-i)[SUP]1/2[/SUP] ]ln{[(1+y)[SUP]1/2[/SUP]+(1-i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]-(1-i)[SUP]1/2[/SUP]]}


&#10233;f(x,y)= -2(1+x)-[SUP]1/2[/SUP]+[SUP]1[/SUP]/[SUB]2[/SUB]ln(1+y[SUP]2[/SUP])-[(1-i)/2(1+i)[SUP]1/2[/SUP]]ln{[(1+y)[SUP]1/2[/SUP]+(1+i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]-(1+i)[SUP]1/2[/SUP]]}-[(1+i)/2(1-i)[SUP]1/2[/SUP] ]ln{[(1+y)[SUP]1/2[/SUP]+(1-i)[SUP]1/2[/SUP]]/[(1+y)[SUP]1/2[/SUP]-(1-i)[SUP]1/2[/SUP]]}=0


is another implicit solutionto the above DE in Question1
 
Heheh kama ulifika hadi huku basi ulijitahidi maana hii makitu ni ya A-Level au Chuo...

Wale waliosoma Additional O-Level waliinusa nusa tu kwa mbaliiiii
Kule kwenye Vitabu vya Backhouse 2 na C. J . Tranter hizi makitu zipo sana.
 
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