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2 years ago

ONLY ANSWER IF YOU KNOW, SHOW WORK

Mathematics

1 answer:

yulyashka [42]2 years ago

6 0

Answer:

hello,

Step-by-step explanation:

$cos(3\theta)+cos(4\theta)\\\\=2*cos(\dfrac{4\theta+3\theta}{2} )*cos(\dfrac{4\theta-3\theta}{2} )\\\\\boxed{=2*cos(\dfrac{7\theta}{2} )*cos(\dfrac{\theta}{2} )}$

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What is true about AngleQRT? Select two options.

stiv31 [10]

The complete question is

"Triangle QST is isosceles, and Line segment R T bisects AngleT. Triangle Q S T is cut by bisector R T. The lengths of sides S T and Q T are congruent. Line segments S R and R Q are congruent. Angles S T R and R T Q are congruent. What is true about AngleQRT?

Select two options. Measure of angleQRT = 90° Measure of angleQRT = Measure of angleSRT AngleQRT Is-congruent-to AngleSTQ Measure of angleQRT = 2*Measure of angleRTQ AngleQRT Is-congruent-to AngleRTQ"

The true about AngleQRT options are A abd B; ∠QRT = 90 and ∠QRT = ∠SRT

<h3>What is the congruent triangle?</h3>

Two triangles are said to be congruent if the length of the sides is equal, a measure of the angles are equal and they can be superimposed.

Given information;

The triangle QST is isosceles with QT ≅ ST.

The ∠STR and ∠RTQ are congruent.

Now, consider two triangles ∠QTR and ∠STR

In the following triangle

TR ≅ TR

QTR ≅ STR

QT ≅ ST

Now, according to SAS rule, two congruent triangles have congruent corresponding to their sides,

1. QR ≅ SR

2. QRT ≅ SRT

Since the above two angles are congruent so, they will have the same measure

That will be 90 degree.

Hence, The correct options are; ∠QRT = 90 and ∠QRT = ∠SRT

For more information about congruent visit;

brainly.com/question/13367096

#SPJ1

5 0

1 year ago

What is the value of (-7+3i)-(2-6i)?

IRISSAK [1]

The answer is -9 + 9i. Hope this helped.

3 0

2 years ago

Read 2 more answers

The International Air Transport Association surveys business travelers to develop quality ratings for transatlantic gateway airp

motikmotik

Answer:

The 95% confidence interval for the population mean rating is (5.73, 6.95).

Step-by-step explanation:

We start by calculating the mean and standard deviation of the sample:

$M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{50}(6+4+6+. . .+6)\\\\\\M=\dfrac{317}{50}\\\\\\M=6.34\\\\\\s=\sqrt{\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{49}((6-6.34)^2+(4-6.34)^2+(6-6.34)^2+. . . +(6-6.34)^2)}\\\\\\s=\sqrt{\dfrac{229.22}{49}}\\\\\\s=\sqrt{4.68}=2.16\\\\\\$

We have to calculate a 95% confidence interval for the mean.

The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.

The sample mean is M=6.34.

The sample size is N=50.

When σ is not known, s divided by the square root of N is used as an estimate of σM:

$s_M=\dfrac{s}{\sqrt{N}}=\dfrac{2.16}{\sqrt{50}}=\dfrac{2.16}{7.071}=0.305$