4 cos² x - 3 = 0
4 cos² x = 3
cos² x = 3/4
cos x = ±(√3)/2
Fixing the squared cosine doesn't discriminate among quadrants. There's one in every quadrant
cos x = ± cos(π/6)
Let's do plus first. In general, cos x = cos a has solutions x = ±a + 2πk integer k
cos x = cos(π/6)
x = ±π/6 + 2πk
Minus next.
cos x = -cos(π/6)
cos x = cos(π - π/6)
cos x = cos(5π/6)
x = ±5π/6 + 2πk
We'll write all our solutions as
x = { -5π/6, -π/6, π/6, 5π/6 } + 2πk integer k
To find the zeroes you make the function equal to zero and then solve.

Then factor out the x to get a quadratic inside the parentheses.

Factor the inside quadratic formula.

Lastly, use the zero product property to solve.

Answer:
if you look at carefully the left triangle has two same side. so left-angle of C is 180-130=50 degree 5x+5x+50=180 x=13 degree
Step-by-step explanation:
for right triangle again one angle is 50 degree and other is 6*13-(3)=75 degree so 75+50+(10y+5)=180 degree y=5 degree
Answer:
Below.
Step-by-step explanation:
y + 2 > -3(x + 1)
y + 2 > -3x - 3
y > -3x - 5
The graph will be the graph of the line y = -3x - 5 (dotted line), with the area above the line shaded.