(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

How to find the conditions on the coefficients of a quadratic equation for the roots to be outside the unit circle eg bx^2 + x - 1 = 0 where b is a constant How do we find the condition(s) that b must satisfy such that the roots of the quadratic lie outside the unit circle (ie modulus greater than one)

2. Relevant equations

bx^2 + x - 1 = 0

3. The attempt at a solution

Solve quadratic eqn with the quadratic formulae

We get to -1+/- * sqrt(1+4a) < -2a

This gradually leads to a contradiction.

Many thanks

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# Homework Help: Find conditions on coefficients of a quadratic so the roots are not in unit circle

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