Question

solve the equation for 0 less than and equal to x less than 2pi.
4cos^2x-3=0
Thanks.

Answer 1

cos^2x = 3/4
(cosx)^2 = 3/4
cosx = sqrt(3)/2
Do you know what to do next? Solve for x.

Answer 2

The equation is :
\[4\cos^2x-3=0\]
So :
\[4\cos^2x=3\]
then :
\[\cos^2x=\frac34\]
so :
\[\cos x=\pm\frac{\sqrt3}2\]
so the possible values of x are :
\[\frac\pi6,~\pi-\frac\pi6,\pi+\frac\pi6, 2\pi-\frac\pi6\]

Answer 3

thank you :)