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pLuvia
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solve the quadratic equation
ix2 - 2(i+1)x + 10 = 0
ix2 - 2(i+1)x + 10 = 0
use quadratickadlil said:solve the quadratic equation
ix2 - 2(i+1)x + 10 = 0
sub the conjugate root in equationkadlil said:If I need to prove it, how do I prove it?
You're allowed to just assume it. However, you have to first recognise that the polynomial has real coefficients. Basically you say "P(x) has real coefficients hence if it has a complex root then the conjugate must also be a root. 1 - 2i is a root ∴ 1 + 2i is also a root." If you're looking for proofs there's a couple in a previous thread (I've never seen a question where they asked for a general proof):kadlil said:If 1-2i is one root of [an eqn] find the other root
Is it possible to just say 1+2i because it is the conjugate of it? Or do I need proof?