Answer:
Step-by-step explanation:
sen(x)=0.5
3cos(x)-4cos^3(x)=0
Remember:
cos^3(x)=cos(x)*cos^2(x)
3cos(x)-4(cos(x)*cos^2(x))=0
we have :
cos^2(x)=1-sin^2(x)
Then:
3cos(x)-4(cos(x)*(1-sin^2(x)))=0
sin^2(x)=(0.5)^2=0.25
3cos(x)-4(cos(x)*(1-0.25))=0
3cos(x)-4(cos(x)*(0.75))=0
Finally
3cos(x)-3cos(x)=0
