Given that 2-3i is a root to the equation z^3+pz^2+qz-13p=0, show that p=-2 and q=5.

Substitute 2-3i into equation using part i (2-3i)3=-46-9i.  -46-9i+p(-5-12i)+q(2-3i)-13p=0. -46-18p+2q-9i-12pi-3iq=0. Real: -46-18p+2q=0 and Imaginary: -9-12p-3q=0. p=-2, q=5

WN
Answered by William N. Maths tutor

11077 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

How do you use factor theorem to show an algebraic term is a factor of a polynomial?


Differentiate the following: 3/2 x^(3/4) + 1/3 x^(-1/4)


Find the derivative with respect to x and the x-coordinate of the stationary point of: y=(4x^2+1)^5


Find the equation of the tangent line to the parabola y=x^2+3x+2 at point P(1, 6).


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning