SOLUTION: write a quadratic equation whose solutions are 1+2i and 1 - 2i the equation is x^2-_x+_=0

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Question 987166: write a quadratic equation whose solutions are 1+2i and 1 - 2i
the equation is x^2-_x+_=0

Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
(x - (1+2i))*(x - (1-2i)).

The constant term is the product  (1+2i)*(1-2i) = 1%5E2 - %282i%29%5E2 = 1 - 4*(-1) = 1 + 4 = 5.

The coefficient at  x  is  -[(1+2i) + (1-2i)] = -2.

Hence,  the quadratic equation is

x%5E2 - 2x + 5 = 0.