Find the volume........

For what value of theta does sin 2theta = cos(theta+30)? Show steps

kolbaska11 [484]

Answer: Ф = 20

Step-by-step explanation:

sin2Ф = cos (Ф+ 30 )

if sinα = cosβ , then α and β are complementary ,that is they add up to be $90^{0}$ .

Therefore : 2Ф + Ф + 30 = 90

3Ф + 30 = 90

3Ф = 90 - 30

3Ф = 60

Ф = 20

8 0

3 years ago

Please help me with my measurement 2 last questions. Edit : please read 8 carefully.

iragen [17]

The different units of measurement (millimeters, centimeters, meters and kilometers) are used to measure from very short distances such as the amount of a medicine in a syringe to long distances between cities.

<h3>What are units of measure?</h3>

Measurement units are a series of references that are used to measure different elements and factors. Specifically, the units of measure for distance measure the distance between two points.

However, not all units of measure work for all situations, for example:

Millimeters are a unit of measurement for very short distances such as millimeters of medication in a syringe.
Centimeters are a unit of measurement for average distances such as the height of a person or the size of some objects.
Meters are a unit of measurement for large distances such as the dimensions of a house.
Kilometers are a unit of measurement for very large distances such as the distance between two cities or countries.

Learn more about distance in: brainly.com/question/15172156

#SPJ1

6 0

2 years ago

Why do we use newton's

inessss [21]

depends. for example: we use his telescopes to see farther. we use his laws of motion to understand certain events that are mostly on said motion

3 0

3 years ago

1 point) As reported in "Runner's World" magazine, the times of the finishers in the New York City 10 km run are normally distri

BigorU [14]

Answer:

(a) E (X) = 61 and SD (X) = 9

(b) E (Z) = 0 and SD (Z) = 1

Step-by-step explanation:

The time of the finishers in the New York City 10 km run are normally distributed with a mean,μ = 61 minutes and a standard deviation, σ = 9 minutes.

(a)

The random variable X is defined as the finishing time for the finishers.

Then the expected value of X is:

E (X) = 61 minutes

The variance of the random variable X is:

V (X) = (9 minutes)²

Then the standard deviation of the random variable X is:

SD (X) = 9 minutes

(b)

The random variable Z is the standardized form of the random variable X.

It is defined as: $Z=\frac{X-\mu}{\sigma}$

Compute the expected value of Z as follows:

$E(Z)=E[\frac{X-\mu}{\sigma}]\\=\frac{E(X)-\mu}{\sigma}\\=\frac{61-61}{9}\\=0$

The mean of Z is 0.

Compute the variance of Z as follows:

$V(Z)=V[\frac{X-\mu}{\sigma}]\\=\frac{V(X)+V(\mu)}{\sigma^{2}}\\=\frac{V(X)}{\sigma^{2}}\\=\frac{9^{2}}{9^{2}}\\=1$

The variance of Z is 1.

So the standard deviation is 1.

8 0

3 years ago

Polygon y is a scaled copy of polygon x using a scal factor of 1/3. Polygon y area is what fraction of polygon x area

Ksenya-84 [330]

9514 1404 393

Answer:

1/9

Step-by-step explanation:

The ratio of areas is the square of the scale factor for linear dimensions.

Area(y)/Area(x) = (1/3)^2 = 1/9

4 0

3 years ago