Answer:
C
Step-by-step explanation:
Step 1: Determine the value of x by using [tex]x=tan^{-1}(\frac{\sqrt{3} }{\sqrt{2}} )[/tex]
[tex]x=tan^{-1}(\frac{\sqrt{3}}{\sqrt{2} })=50.7685 degrees[/tex]
Step 2: Substitute x=50.7685 degrees into the original equation
[tex]2cos^{4}(x)-sin(x)=2cos^{4} (50.7685)-sin(50.7685)=0.320-0.7746=-0.4546[/tex]
