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
marysya [2.9K]
3 years ago
14

Save me the headache

Mathematics
2 answers:
vichka [17]3 years ago
8 0

Answer:

Simple tell everyone around you to be quiet and to keep quiet

if u have a headache

Step-by-step explanation:

maxonik [38]3 years ago
5 0

(9\sin2x+9\cos2x)^2=81

Taking the square root of both sides gives two possible cases,

9\sin2x+9\cos2x=9\implies\sin2x+\cos2x=1

or

9\sin2x+9\cos2x=-9\implies\sin2x+\cos2x=-1

Recall that

\sin(\alpha\pm\beta)=\sin\alpha\cos\beta\pm\cos\alpha\sin\beta

If \alpha=2x and \beta=\dfrac\pi4, we have

\sin\left(2x+\dfrac\pi4\right)=\dfrac{\sin2x+\cos2x}{\sqrt2}

so in the equations above, we can write

\sin2x+\cos2x=\sqrt2\sin\left(2x+\dfrac\pi4\right)=\pm1

Then in the first case,

\sqrt2\sin\left(2x+\dfrac\pi4\right)=1\implies\sin\left(2x+\dfrac\pi4\right)=\dfrac1{\sqrt2}

\implies2x+\dfrac\pi4=\dfrac\pi4+2n\pi\text{ or }\dfrac{3\pi}4+2n\pi

(where n is any integer)

\implies2x=2n\pi\text{ or }\dfrac\pi2+2n\pi

\implies x=n\pi\text{ or }\dfrac\pi4+n\pi

and in the second,

\sqrt2\sin\left(2x+\dfrac\pi4\right)=-1\implies\sin\left(2x+\dfrac\pi4\right)=-\dfrac1{\sqrt2}

\implies2x+\dfrac\pi4=-\dfrac\pi4+2n\pi\text{ or }-\dfrac{3\pi}4+2n\pi

\implies2x=-\dfrac\pi2+2n\pi\text{ or }-\pi+2n\pi

\implies x=-\dfrac\pi4+n\pi\text{ or }-\dfrac\pi2+n\pi

Then the solutions that fall in the interval [0,2\pi) are

x=0,\dfrac\pi4,\dfrac\pi2,\dfrac{3\pi}4,\pi,\dfrac{5\pi}4,\dfrac{3\pi}2,\dfrac{7\pi}4

You might be interested in
Find the number of terms and the degree of this polynomial.
dangina [55]

Answer:

Number of terms:3

Degree:2nd degree

Step-by-step explanation:

-5c^2 +8c +2-3

-5c^2 +8c-1

he 2nd degree is the power of 2

5 0
3 years ago
Davens pays $50 each week for guitar lessons. How much will he pay after 3/4 of a year
Alja [10]
You’ve got to work out 3/4 of the year first, that’s 75%, after you need to work out how many weeks are in those days so you divide it by 7 then divide that answer by $50 and hopefully you get your answer. hope this helps
5 0
3 years ago
Read 2 more answers
An audio cable is 14.5 dm long. How long is the cable in meters?
Oduvanchick [21]

Answer:

1.45 meters

Step-by-step explanation:

7 0
2 years ago
Read 2 more answers
Which equation represents a proportional relationship?
notsponge [240]

Which equation represents a proportional relationship?

C. y=1/2x+3

5 0
3 years ago
Dylan opened a credit card account with $650.00 of available credit. Now that he has made some purchases, Dylan’s account only h
sergeinik [125]

Answer:

32.5%

Step-by-step explanation:


7 0
3 years ago
Other questions:
  • henry and his brother each start a savings account. henry begins with $200 and deposits $25 each month. his brother begins with
    5·1 answer
  • What is the solution for x. 4/3x-1/3=9
    7·1 answer
  • A manager recorded how many hours each of 11 cashiers worked in a week. Which interval contains the median number of hours worke
    15·1 answer
  • Graph 12 gallons per minute
    7·1 answer
  • What is 3x2 + 21x + 18 in factored form?
    14·1 answer
  • Which statement accurately describes how to reflect point A(3,-1) over the y-axis?
    14·1 answer
  • A falcon flying at a height of 150 yards spots a sparrow flying at a height of 50 yards. The location of the sparrow makes an an
    10·1 answer
  • ASAP PLS ANSWER!!! TY!
    9·2 answers
  • show that the lines x2-4xy+y2=0 and x+y=3 form an equilateral triangle also find area of the triangle
    12·1 answer
  • Which equation represents this situation?
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!