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:
Height of skyscraper's model = 5 feet
Step-by-step explanation:
Given:
Height of skyscraper = 1,450 feet
Scale model ratio = 1:290
Find:
Height of skyscraper's model.
Computation:
Height of skyscraper's model = Height of skyscraper × Scale model ratio
Height of skyscraper's model = 1,450 × (1/290)
Height of skyscraper's model = 5 feet
Answer:
80
Step-by-step explanation:
PEMDAS- do exponents first here, simplifying that to 64+16, add those to get 80.
Answer:
23
Step-by-step explanation:
plug -2 in for x then solve
