9709 MATHS P3 O/N 2009 32 {Q7 (ii), (iii), (iv}

[gentleman]

I have a small doubt in complex numbers....
PLZ can anyone help me in doing these 3 subparts
MATHS P3 O/N 2009 32 {Q7 (ii), (iii), (iv}

 

[Mortal9090]

buy the book by redpost yearly solved, goto tariq book city

 

[ahmed t]

argument of u/v is the argument of u - the argument of v
angle of AOB
is the argument of A - the argument of B
OA and BC are of the same length and are parallel to each other
they make two sides of a rectangle

 

[gentleman]

please anyone!! its urgent :%)

 

[Madiha :)]

ii) u/v= -1/2 + 1/2 i
so arg wil b tan inverse ( 0.5/0.5) which wil b pie/4 .. dis is the basic angle .. -0.5+0.5i is in 2nd quad so u wil have to subctract it from pie .
hence, pie-pie/4 = 3pie/4.

 

[ahmed t]

for ii) the argument of u is
180-tan^-1(1/2)
and for v it is just tan^-1(1/3)
minus arg v from u and u will get 3pi/4

 

[ahmed t]

using madihas way is much better because u already found out u/v in the question before , but my explanation is just to clear up ur PM doubt