This is just converting billion to million, vice-versa.
1 million = 0.001 billion
1,200 billion = 1,200,000,000,000
So once it is converted, the answer will be,
1.2 x 10^15 million.
The slope intercept form is y=mx+b
in this case y=-x
y=(-1)x + 0
so the slope m=-1 and y-intercept which is b is 0
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