1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
zhannawk [14.2K]
3 years ago
9

How do I solve these trigonometric equations!!?

Mathematics
1 answer:
ValentinkaMS [17]3 years ago
3 0
<span>1) (sin x)(cos x) = 0 This means that either sin x = 0, or cos x = 0. Sin x = 0 when x = 0 or pi. cos x = 0 when x = pi/2 or 3pi/2. 2) cos2x + 2cosx + 1 = 0 First, expand cos2x. Simple trigonometric identity states that cos2x = (cos x)^2 - (sin x)^2.Now, substituting this equation, we get cos2x + 2cosx + 1 = (cos x)^2 - (sin x)^2 + 2cosx + 1. Note that we can now utilize the identity (cos x)^2 = 1 - (sin x)^2 to obtain (cos x)^2 + 2cosx + 1 - (sin x)^2 = 2(cos x)^2 + 2(cos x) = 0. Now, we can see that 2(cos x)^2 + 2(cos x) = 2(cos x)(cos x + 1) = 0. This is true when cos x = 0 or cos x + 1 = 0. Cos x = 0 when x = pi/2 or 3pi/2. cos x = -1 when x = pi. Therefore, x = pi/2, pi or 3pi/2.</span>
You might be interested in
Which of the following is between 0.40 and 0.47?
tatyana61 [14]
The answer is C. 21/50 is 0.42. 7/50 is 0.14. 19/50 is 0.38. 43/50 is 0.86. To convert a fraction to a decimal, you will have to divide the numerator by the denominator.
Hope this helped.
6 0
3 years ago
Howard is designing a chair swing ride. The swing ropes are 4 44 meters long, and in full swing they tilt in an angle of 2 3 ∘ 2
qaws [65]

Question:

Howard is designing a chair swing ride. The swing ropes are 4 meters long, and in full swing they tilt in an angle of 23°. Howard wants the chairs to be 3.5 meters above the ground in full swing. How tall should the pole of the swing ride be? Round your final answer to the nearest hundredth.

Answer:

7.18 meters

Step-by-step explanation:

Given:

Length of rope, L = 4 m

Angle = 23°

Height of chair, H= 3.5 m

In this question, we are to asked to find the height of the pole of the swing ride.

Let X represent the height of the pole of the swing ride.

Let's first find the length of pole from the top of the swing ride. Thus, we have:

cos \theta = \frac{h}{L}

Substituting figures, we have:

cos(23) = \frac{h}{4}

Let's make h subject of the formula.

h = 4cos(23) = 3.68

The length of pole from the top of the swing ride is 3.68 meters

To find the height of the pole of the swing ride, we have:

X = h + H

X = 3.68 + 3.5

X = 7.18

Height of the pole of the swing ride is 7.18 meters

3 0
3 years ago
Solve:<br> 12 + 5 + 3’2 x 10 - 5 = <br> (12 + 5) + 3'2 x (10 – 5) =
kondaur [170]

Answer:

1) 102

2) 62

Step-by-step explanation:

12 + 5 + 3²  × 10 - 5

12 + 5 + 9 × 10 - 5

12 + 5 + 90 - 5

17 + 90 - 5

107 - 5

102

(12+5) + 3² × (10 - 5)

(17) + 9 × (5)

17 + 45

62

4 0
3 years ago
Read 2 more answers
Is 1.29 more than 1.202
steposvetlana [31]
Yes because 9 is bigger than 0.

5 0
3 years ago
Read 2 more answers
HELP ASAP ILL GIVE U BRAINLIEST AND A THANKS
Olenka [21]

Answer:

you have to write it down on a piece of paper and go from there

Step-by-step explanation:

5 0
3 years ago
Other questions:
  • Which describes the intersection of planes A and B?<br> line CD<br> line ED<br> point C<br> point D
    14·2 answers
  • Karla has spent $39 on food. She bought milk, cheese, and meat. The milk cost half as much as the cheese and the meat cost 4 tim
    15·1 answer
  • Is -3.16227766017 a rational or irrational number?
    11·2 answers
  • How many pounds of newspapers did Mrs. Tobia's class recycle?​
    5·1 answer
  • To get ready for the big community bake sale, a baker is baking cookies. For his first batch...
    11·2 answers
  • What is 2/5 ÷ (25% of 1)?​
    11·1 answer
  • This question is designed to be answered without a calculator. Use the antiderivative formula shown, where f(u) represents a fun
    6·1 answer
  • Solve the expression for a=12, b=6 and c=3 <br> Look at the picture will give Brainlist !
    11·2 answers
  • I need the x and y value<br><br><br> I did it and I got 26 got both, but I’m not sure.
    15·2 answers
  • 4×____×1=12 ?=____. please help me solve this question​
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!