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find the real values of x and y for which the complex numbers-3 +ix^2y and x^2+y+4i are conjugate of each other
Hint :- consider two equation \(-3+i x^2y=x^2+y-4i\) \(x^2+y+4i=-3-ix^2y\)
They are the same thing
I think there was a typo in the question http://www.wolframalpha.com/input/?i=solve+x%5E2%2By%3D-3%2C+x%5E2y%3D-4+in+reals
also u can do this trick (i still don't know which one will solve it lol ) \((-3 +ix^2y)(x^2+y+4i )= (9-x^4y^2)=((x^2+y)^2-16))\)
what are the options @No.name
No options given but the answer is x=1, y= -4 x=-1 y=-4
\(−3+ix^2y=x^2+y−4i \) means that \(x^2+y=-3\) \(x^2y=-4\)
for \(x^2y=-4\) since you wanna real then \(x =2,\sqrt2 ,1\) y=-1,-2,-4 try to find wich pair satisfy first equation \((2,-1) (\sqrt 2 , -2) (1,-4) \)
so basically is it trial and error
also take negative side , it works
basicly you need to know the proposition if C1,c2 both complex number \(C_1=x_1+iy_1\) \(C_2=x_2+iy_2\) then \(C_1 = C_2\iff x_1=x_2 \text{ and } y_1=y_2\)
and you need to know how to construct conjugate of complex number ..
x^2 y = -4 x^2 +y = -3 I got these two equations then what i should do
ok , when you got x^2 y = -4 factorize -4
or solve like equation x^2=-3-y and x^2=-4/y
or you can solve them by substitution : x^2y = -4 y = -4/x^2 substitute this in second equation and solve x
Yessssss , got the answer , couldn't reply because of slow internet
In the second equation we would have to substitute that then again substitute x^2 with a variable
exactly ! x^2 +y = -3 x^2 -4/x^2 = -3 t^2 +3t - 4 = 0 (t+4)(t-1) = 0 t = 1 or -4 discard -4
Even i substituted the same variable "t" (although it dosen't matter) hehe gone are the days to substitute x's and y's
haha! so basically two complex numbers equal IF AND ONLY IF their real parts are equal, and their imaginary parts are equal
i think @ikram002p said that earlier..
yes
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