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3 years ago

Trig///HELPP PLEASE!! i’ve been stuck on this for 30 minutes!!

Mathematics

1 answer:

ddd [48]3 years ago

8 0

Answer: There are two solutions and they are

theta = 135

theta = 225

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Explanation:

Recall that x = cos(theta). Since the given cosine value is negative, this indicates x < 0. Theta is somewhere to the left of the y axis, placing it in quadrant 2 or quadrant 3.

It turns out there are two solutions, with one solution per quadrant mentioned above. Use the unit circle to find that the two solutions are:

theta = 135

theta = 225

You're looking for points on the unit circle that have x coordinate equal to x = -sqrt(2)/2. Those two points correspond to the angles of 135 and 225, which are in quadrants 2 and 3 respectively.

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I recommend using your calculator to note that

-sqrt(2)/2 = -0.70710678

cos(135) = -0.70710678

cos(225) = -0.70710678

The decimal values are approximate. Make sure your calculator is in degree mode. Because those three results are the same decimal approximation, this indicates that cos(135) = cos(225) = -sqrt(2)/2.

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The value, V (t), in dollars, of a stock t months after it is purchased is modeled by the following equation.

11Alexandr11 [23.1K]

Answer:

Step-by-step explanation: $V(t)= 42(1-e ^{1.5t} ) +36$ is given value in dollars of a stock in t months after it is purchased.

a) Substitute 1 for t

$V(1) = 42(1-e^{-1.5} )+36 \\=67.852\\=67.85$

V(12) = $V(1) = 42(1-e^{-1.5*12} )+36 \\=77.00$

b) Find derivative for V

$V'(t) = 42(-1.5) e^{-1.5t} )\\\\=-63e^{-1.5t}$

c) When V(t) = 75

$V(t)=75= 42(1-e ^{1.5t} ) +36\\1-e ^{1.5t=0.9286\\=-2.639$

d) As t tends to infinity, exponent being in negative t tends to 0

So V tends to 42(1-0)+36 = 78

3 0

3 years ago

1. Name angle 'x' <br><br>2. calculate the size of angle 'y' <br><br>

Burka [1]

Answer:

Step-by-step explanation:

x = 35° (opposite agles)

y = 180 - 35 - 75

y = 70

-----------------------

check 35 + 75 + 70 = 180°

the answer is good

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2 years ago

Ax-by/c =d solve for x

wolverine [178]

Answer: x = (cd + by) / a

Working out:

(ax - by) / c = d

1)Multiply by c on both sides to get:
ax - by = cd

2) Add by on both sides to get:
ax = cd + by

3) divide by a on both sides to get:
x = (cd + by) / a

4 0

3 years ago

I met a man who said, if you can guess my age, I will pay you one dollar for each year that I have lived . I will also give you

Vladimir79 [104]

He could be 40321 years old.
If you divide 40321 by any odd or even number between 1 and 9, the remainder is 1.

I got this number by doing (2*3*4*5*6*7*8) + 1

4 0

3 years ago

Read 2 more answers

Which inequality is true 1.5 > 2 1/2, 1/2 > 0.5, -2.5 > -1.5, -3 1/2 > - 4.5

yawa3891 [41]

Answer: D

Step-by-step explanation:

(A. 1.5 > 2 1/2

(B. 1/2 > 0.5

(C. -2.5 > -1.5

(D. -3 1/2 > - 4.5

Step 1: Convert everything to decimals or fractions so its easier to see and make it less likely to get the question wrong

Method #1: Fractions

1.5= 1 1/2

0.5= 1/2

-2.5= - 2 1/2

-1.5= - 1 1/2

-4.5= -4 1/2

Now we have:

(A. 1 1/2 > 2 1/2 --> This is wrong because 1 1/2 is supposed to be less than 2 1/2.

(B. 1/2 > 1/2 This is also wrong. 1/2 is equal to 1/2; they are obviously the same.

(C. -2 1/2 > -1 1/2 This is wrong because, in negative numbers, its sort of backwards. For example, -2 is actually less than -1 because its farther away from 0. But if they were normal positive numbers, 2 would be bigger. But here, -2 1/2 is less than -1 1/2.

(D. -3 1/2 > - 4 1/2 This is correct. -3 1/2 is closer to 0 than -4 1/2, so it has to be bigger.

Solving the problem this way gets me to: Answer= D

Method #2: Decimals (remember: same numbers, different way of writing them!!!)

(A. 1.5 > 2.5 False. 1.5 is less than 2.5

(B. 0.5 > 0.5 False. 0.5 is equal to 0.5

(C. -2.5 > -1.5 False. -2.5 is farther away from 0 so its actually smaller.

(D. -3.5 > - 4.5 True. -3.5 is closer to 0.

Doing it this way also leads me to Answer= D.

Hope this helps :)) Also can i please have brainiest? I worked pretty hard on this :D

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2 years ago

Read 2 more answers