The complex number 2 + 4i is one of the root to the quadratic equation
x^2 + bx + c = 0, where b and c are real numbers.
a) Find b and c
b) Write down the second root and check it.

• always in a qudratic equation if we got a complex root the other root is the complex conjugate of the first one.
  here x1=2+4i then x2=2-4i;
  taking these two solution we can write {x-(2+4i)}{x-(2-4i)};then we will get the equation as x^2-4x+20..... so b=-4,c=20
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