James knows that when h walks, he takes about 120 steps per minute and that each step is 2.75 feet long. Which calculation is mo
2 answers:
You might be interested in
The given complex number is
z = 1 + cos(2θ) + i sin(2θ), for -1/2π < θ < 1/2π
Part (i)
Let V = the modulus of z.
Then
V² = [1 + cos(2θ)]² + sin²(2θ)
= 1 + 2 cos(2θ) + cos²2θ + sin²2θ
Because sin²x + cos²x = 1, therefore
V² = 2(1 + cos2θ)
Because cos(2x) = 2 cos²x - 1, therefore
V² = 2(1 + 2cos²θ - 1) = 4 cos²θ
Because -1/2π < θ < 1/2π,
V = 2 cosθ PROVEN
Part ii.
1/z = 1/[1 + cos2θ + i sin 2θ]
The denominator is
Therefore
The real part of 1/ = 1/ (constant).
z = 1 + cos(2θ) + i sin(2θ), for -1/2π < θ < 1/2π
Part (i)
Let V = the modulus of z.
Then
V² = [1 + cos(2θ)]² + sin²(2θ)
= 1 + 2 cos(2θ) + cos²2θ + sin²2θ
Because sin²x + cos²x = 1, therefore
V² = 2(1 + cos2θ)
Because cos(2x) = 2 cos²x - 1, therefore
V² = 2(1 + 2cos²θ - 1) = 4 cos²θ
Because -1/2π < θ < 1/2π,
V = 2 cosθ PROVEN
Part ii.
1/z = 1/[1 + cos2θ + i sin 2θ]
The denominator is
Therefore
The real part of 1/ = 1/ (constant).
Answer:
4.25 feet of ribbon cost around $ 8.29
Step-by-step explanation:
We are given the following information in the question:
Length of ribbon to be bought by Brenna = 4.25 feet
Cost of 1 foot of ribbon = $1.95
Total or actual cost of the ribbon =
Cost of ribbon to be purchased by Brenna =
Thus, to find the actual cost Brenna should use the product of total length of ribbon to be bought and the unit cost of the ribbon.
Hence, 4.25 feet of ribbon cost around $ 8.29