Answer:
A. 60*
Step-by-step explanation:
I used the website M A T H W A Y . C O M
and I remember learning this in my school, I worked this problem by hand and am confident that A is the correct answer.
Answer:
60°
A is correct
Step-by-step explanation:
Given: [tex]4\cos^2x-1=0[/tex]
[tex]4\cos^2x=1[/tex]
Divide by 4
[tex]\cos^2x=\dfrac{1}{4}[/tex]
Taking square root both sides
[tex]\cos x=\pm \dfrac{1}{2}[/tex]
[tex]\cos x=\dfrac{1}{2}[/tex] or [tex]\cos x=-\dfrac{1}{2}[/tex]
[tex]x=\cos^{-1}(\dfrac{1}{2})[/tex] or [tex]x=\cos^{-1}(-\dfrac{1}{2})[/tex]
[tex]x=60^\circ,300^\circ[/tex] or [tex]x=120^\circ,240^\circ[/tex]
Hence, x=60° is correct
