Pogggggggggggggggers

pentagon [3]

Answer:

you should download the app Socratic it lets you take a picture of the problem and shows you step by step how to solve it. it also gives you multiple resources to get the answer

5 0

3 years ago

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

kirza4 [7]

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:

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

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

4 0

2 years ago

Read 2 more answers

Share £747 in the ratio 2:7 between Tom and Ben.<br> Tom will get<br> £<br> Ben will get<br> £

kari74 [83]

<em> $tom \: will \: get \:£166 \\ ben \: will \: get \: £581\\ solution \\ let \: the \: ratios \: be \: 2x \: and \: 7x \\ 2x + 7x = 747 \\ or \: 9x = 747 \\ or \: x = \frac{747}{9} \\ x = £83 \\ replacing \: value \\ 2x \\ = 2 \times 83 \\ = 166 \\ 7x \\ = 7 \times 83 \\ = 581 \\ hope \: it \: helps$ </em>

5 0

3 years ago

Find the values of a and b that make f continuous everywhere. f(x) = x^2 − 4 / x − 2 if x < 2 ax^2 − bx + 3 if 2 ≤ x < 3 4

inysia [295]

<span>Find the values of a and b that make f continuous everywhere. f(x) = x^2 − 4 / x − 2 if x < 2 ax^2 − bx + 3 if 2 ≤ x < 3 4x − a + b if x ≥ 3 </span>
a=7/12
b=13/2

4 0

3 years ago

The temperature went from -12°F to 18°F. Which of the following expressions could be used to find how much the temperature chang

jeyben [28]

Answer:

4. 18-(-12)

Step-by-step explanation:

so i basically took 12 and added that to 18 [and got 30] to find out how many degrees it went up and then i solved each equation till i got 30. I hope this helped and that you could understand the way i did it.

3 0

2 years ago