QCEVault

Further complex numbers — Question 176

Original QCE Vault practice · 5 marks

Q176 · Practice questionTechnology-freeComplex familiar5 marks

QUESTION 176 (5 marks)

The polynomial p(z)=z3−4z2+9z−10p(z)=z^3-4z^2+9z-10 has zero 1+2i1+2i.
a)
Factorise p over the real numbers and determine all its zeros.
[3 marks]
b)
Determine which zero lies nearest the origin, with justification.
[2 marks]
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