<ol class="abc-list"><li><div class="list-item-paragraph">Show that the equation \(2\sin^2{x}+3\cos{x}=0\) can be written in the form \(a\cos^2{x}+b\cos{x}+c=0\), where&nbsp;\(a, b\) and\(c\) are integers to be found.<span class="inline-marks">[2]</span></div></li><li><div class="list-item-paragraph">Hence, or otherwise, solve the equation \(2\sin^2{x}+3\cos{x}=0\) for&nbsp;\(-180^{\circ}\leq x\leq 180^{\circ}\).<span class="inline-marks">[3]</span></div></li></ol>

Show that the equation \(2\sin^2{x}+3\cos{x}=0\) can be written in the form \(a\cos^2{x}+b\cos{x}+c=0\), where \(a, b\) and\(c\) are integers to be found.

Hence, or otherwise, solve the equation \(2\sin^2{x}+3\cos{x}=0\) for \(-180^{\circ}\leq x\leq 180^{\circ}\).

Trigonometric Equations and Identities

International Baccalaureate Standard Level Mathematics