Change of Sign (AQA A-Level Mathematics): Flashcards

Find roots of equation $f(x) = 0$

Where function changes positive to negative or vice versa

Find interval $[a, b]$ where $f(a)$, $f(b)$ have opposite signs

Decimal search or interval bisection

In interval where change of sign occurs

Function is continuous and root isn't repeated

Approximate solution for equations hard to solve algebraically

Graph crosses the $x$-axis

Check $f(a)$, $f(b)$ have opposite signs, function continuous

$[a - 0.0005, a + 0.0005]$