Quadratic Equation
Level
pending
What is the sum of the roots in the equation C, z8 − 17z 4 + 16 = 0 such that z − |z| = 0?
The answer is 3.
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1 solution
As z-\z\=0 z is always positive. Solve the equation by taking z^4 as x and z^8 as x^2. Hence we get the roots as 1,-1,2,-2. As z is always positive we need to consider only 1and 2. Hence the sum of roots is 3.