Answer:
C
Step-by-step explanation:
Because equation C is telling us that the amount of caffeine is less than 400.
Hope this will help
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
Answer:
aaaannnnnnsssswwweeeerrr fffoooorrrr thhhhhiiisss pppprrroobbllleeemmm is s+14
B. if two lines are perpendicular, then they intersect to form four right angles.
