# 4cos^2x−3=0

Question
Trigonometric Functions
$$\displaystyle{4}{{\cos}^{{2}}{x}}−{3}={0}$$

2021-03-07
$$\displaystyle{4}{\left({\cos}^{{2}}\right)}{x}-{3}={0}$$
$$\displaystyle{4}{\left({\cos}^{{2}}\right)}={3}$$
$$\displaystyle{\left({\cos}^{{2}}\right)}{x}=\frac{{3}}{{4}}$$
$$\displaystyle{\cos{{x}}}=\frac{{\sqrt{{3}}}}{{2}}$$
$$\displaystyle{x}={{\cos}^{{-{{1}}}}{\left(\frac{{\sqrt{{3}}}}{{2}}\right)}}$$
x=30

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