SOLUTION: Write a quadratic equation whose solutions are 2i and -2i in standard form

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Question 922838: Write a quadratic equation whose solutions are 2i and -2i in standard form
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x+=+2i+
+x+=+-2i+
+f%28x%29+=+%28+x+-+2i+%29%2A%28+x+%2B+2i+%29+
+f%28x%29+=+x%5E2+-+4%2Ai%5E2+
+f%28x%29+=+x%5E2+%2B+4+
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check:
solve with quadratic formula
+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
+a+=+1+
+b+=+0+
+c+=+4+
+x+=++sqrt%28+-+4c+%29%2F2+
+x+=+%28+2%2Asqrt%284%29%2Ai+%29+%2F+2+
+x+=+4i+%2F+2+
+x+=+2i+
and also:
+x+=+-2i+
OK