Number of solutions of $\sqrt{3}cos2 heta + 8cos heta + 3\sqrt{3} = 0, heta \in \lbrack - 3\pi,2\

Question

Number of solutions of $\sqrt{3}cos2	heta + 8cos	heta + 3\sqrt{3} = 0,	heta \in \lbrack - 3\pi,2\pibrack$ is:

Accepted Answer

$\sqrt{3}\left( 2\cos^{2}	heta - 1 ight) + 8cos	heta + 3\sqrt{3} = 0$$${2\sqrt{3}\cos^{2}	heta + 8cos	heta + 2\sqrt{3} = 0 }{(\sqrt{3}cos + 1)(cos	heta + \sqrt{3}) = 0 }{cos	heta = - \frac{1}{\sqrt{3}} }$$as $- \sqrt{3}$ (reject)$	herefore	heta =$ will have 5 value in $\lbrack - 3\pi,2\pibrack$

Question

Options

Solution

More Trigonometric Equation Questions