# complex numbersWatch

Thread starter 4 years ago
#1
hi ive got the following question but im just getting really confused

(u+3)/(u-i)=2i where u=a+bi find a and b

any help would be grateful

thank you
0
4 years ago
#2
(Original post by mickymouse1995)
hi ive got the following question but im just getting really confused

(u+3)/(u-i)=2i where u=a+bi find a and b

any help would be grateful

thank you
Put a+bi in place of u, clear your fraction, simplify and equate real and imaginary parts to give a pair of simultaneous equations in a and b
1
4 years ago
#3
Alternatively: Rearrange to get it into the from u = a+ib - no great work required, multipy bu "u-i", rearrange to get u on one side, divide by the coeff of u, simplify your complex no. and there's your answer.
Thread starter 4 years ago
#4
thank you xxx
0
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