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
steposvetlana [31]
2 years ago
10

Which function is the same as y = 3 cosine (2 (x startfraction pi over 2 endfraction)) minus 2? y = 3 sine (2 (x startfraction p

i over 4 endfraction)) minus 2 y = negative 3 sine (2 (x startfraction pi over 4 endfraction)) minus 2 y = 3 cosine (2 (x startfraction pi over 4 endfraction)) minus 2 y = negative 3 cosine (2 (x startfraction pi over 2 endfraction)) minus 2
Mathematics
2 answers:
kirza4 [7]2 years ago
4 0

The function which is same as the function y = 3cos(2(x +π/2)) -2 is: Option A: y= 3sin(2(x + π/4)) - 2

<h3>How to convert sine of an angle to some angle of cosine?</h3>

We can use the fact that:

\sin(\theta) = \cos(\pi/2 - \theta)\\\sin(\theta + \pi/2) = -\cos(\theta)\\\cos(\theta + \pi/2) = \sin(\theta)

to convert the sine to cosine.

<h3>Which trigonometric functions are positive in which quadrant?</h3>
  • In first quadrant (0 < θ < π/2), all six trigonometric functions are positive.
  • In second quadrant(π/2 < θ < π), only sin and cosec are positive.
  • In the third quadrant (π < θ < 3π/2), only tangent and cotangent are positive.
  • In fourth (3π/2 < θ < 2π = 0), only cos and sec are positive.

(this all positive negative refers to the fact that if you use given angle as input to these functions, then what sign will these functions will evaluate based on in which quadrant does the given angle lies.)

Here, the given function is:

y= 3\cos(2(x + \pi/2)) - 2

The options are:

  1. y= 3\sin(2(x + \pi/4)) - 2
  2. y= -3\sin(2(x + \pi/4)) - 2
  3. y= 3\cos(2(x + \pi/4)) - 2
  4. y= -3\cos(2(x + \pi/2)) - 2

Checking all the options one by one:

  • Option 1: y= 3\sin(2(x + \pi/4)) - 2

y= 3\sin(2(x + \pi/4)) - 2\\y= 3\sin (2x + \pi/2) -2\\y = -3\cos(2x) -2\\y = 3\cos(2x + \pi) -2\\y = 3\cos(2(x+ \pi/2)) -2

(the last second step was the use of the fact that cos flips its sign after pi radian increment in its input)
Thus, this option is same as the given function.

  • Option 2: y= -3\sin(2(x + \pi/4)) - 2

This option if would be true, then from option 1 and this option, we'd get:
-3\sin(2(x + \pi/4)) - 2= -3\sin(2(x + \pi/4)) - 2\\2(3\sin(2(x + \pi/4))) = 0\\\sin(2(x + \pi/4) = 0

which isn't true for all values of x.

Thus, this option is not same as the given function.

  • Option 3: y= 3\cos(2(x + \pi/4)) - 2

The given function is y= 3\cos(2(x + \pi/2)) - 2 = 3\cos(2x + \pi) -2 = -3\cos(2x) -2

This option's function simplifies as:

y= 3\cos(2(x + \pi/4)) - 2 = 3\cos(2x + \pi/2) -2 = -3\sin(2x) - 2

Thus, this option isn't true since \sin(2x) \neq \cos(2x) always (they are equal for some values of x but not for all).

  • Option 4: y= -3\cos(2(x + \pi/2)) - 2

The given function simplifies to:y= 3\cos(2(x + \pi/2)) - 2 = 3\cos(2x + \pi) -2 = -3\cos(2x) -2

The given option simplifies to:

y= -3\cos(2(x + \pi/2)) - 2 = -3\cos(2x + \pi ) -2\\y = 3\cos(2x) -2

Thus, this function is not same as the given function.

Thus, the function which is same as the function y = 3cos(2(x +π/2)) -2 is: Option A: y= 3sin(2(x + π/4)) - 2

Learn more about sine to cosine conversion here:

brainly.com/question/1421592

grigory [225]2 years ago
3 0

Answer:

a

Step-by-step explanation:

You might be interested in
3x -4 = x -8 equation ​
bagirrra123 [75]

\\ \sf\longmapsto 3x-4=x-8

\\ \sf\longmapsto 3x-x=8+4

\\ \sf\longmapsto 2x=12

\\ \sf\longmapsto x=\dfrac{12}{2}

\\ \sf\longmapsto x=6

6 0
3 years ago
Describe in words the rule to calculate the area of a rhombus based on its<br> diagonals.
coldgirl [10]

Answer:

area of rhombus = 1/2 d^{1} d^{2}

half * diagonal 1 * diagonal 2 is the area of rhombus.

hope this answer helps you...

please mark as brianliest.. thank you!

6 0
3 years ago
Jeans were $11.50 with a 15% sales tax. What is the sales tax?
lisov135 [29]

Answer:

1.50

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
How do you find mean absolute deviation
DIA [1.3K]
To find the mean absolute deviation of the data, start by finding the mean of the data set.
Find the sum of the data values, and divide the sum by the number of data values.
Find the absolute value of the difference between each data value and the mean: ...
Find the sum of the absolute values of the differences.
And then divide the sum of the absolute values of the differences by the number of data values
5 0
3 years ago
Evaluate the following expression using the values given.
mel-nik [20]

Answer:

-19

Step-by-step explanation:

2×2-2z4+y2-x2+z4

now we put the value,

4-2(2to the power 4)+(3 to the power 2)-(-4 to the power 2)+(2 to the power 4)

4-2×16+9-16+16

4-32+9

4+9-32

13-32

-19

please check the answer again i am sorry if it's wrong

5 0
3 years ago
Other questions:
  • Bill can hit a bucket of 323 golf balls in 17 hours.
    7·2 answers
  • In a right triangle, 40-x=(3x). What is the value of x?
    14·1 answer
  • .
    7·1 answer
  • Please answer this correctly
    11·1 answer
  • Need help please thanks
    10·1 answer
  • 6,18,54,...<br> Find the 9th term.
    15·2 answers
  • Someone help me please <br> whats the square root of 0.0025
    8·1 answer
  • Harry was given an assignment. He had 42 days to get 336 tasks done at work.
    12·1 answer
  • Find the perimeter of ABCD
    12·1 answer
  • Coulddd i be helped really quick?
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!