Jon P. answered 08/06/15
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It isn't clear how this is supposed to look, because the parentheses are ambiguous.
Is it supposed to be this?
-10i - 2√5
------------
5i - √5
Is it supposed to be this?
-10i - 2√5
------------
5i - √5
If so, then to solve it you multiply the numerator and denominator by the complex conjugate of the denominator, which is 5i + √5. Then you get:
-10i - 2√5 5i + √5 -2(5i + √5)(5i + √5) -2(25i2 + 5√5 i + 5√5 i - √5*√5)
------------ ---------- = ------------------------- = -------------------------------------- =
5i - √5 5i + √5 (5i - √5)(5i + √5) 25i2 - 5
-2(-25 + 5 + 10√5 i) / (-25 - 5) =
-2(10√5 i - 20) / (-30) =
-20(√5 i -2 ) / (-30) =
(2/3) (√5 i - 2)
But please review the calculations to make sure that you agree with everything.
Nelly D.
08/06/15