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
anygoal [31]
3 years ago
14

Find the exact value for the expression under the given conditions.

Mathematics
2 answers:
Romashka [77]3 years ago
3 0

Answer:

By  Pythagoras,

\displaystyle{r}=\sqrt{{{x}^{2}+{y}^{2}}}r=x2+y2 \displaystyle=\sqrt{{{\left(-{2}\right)}^{2}+{3}^{2}}}=(−2)2+32 \displaystyle=\sqrt{{{4}+{9}}}=\sqrt{{13}}=4+9=13

For this example, we define the trigonometric ratios for θ in the following way:

\displaystyle \sin{\theta}=\frac{y}{{r}}=\frac{3}{\sqrt{{13}}}={0.83205}sinθ=ry=133=0.83205

\displaystyle \cos{\theta}=\frac{x}{{r}}=\frac{{-{2}}}{\sqrt{{13}}}=-{0.55470}cosθ=rx=13−2=−0.55470

\displaystyle \tan{\theta}=\frac{y}{{x}}=\frac{3}{ -{{2}}}=-{1.5}tanθ=xy=−23=−1.5

 

\displaystyle \csc{\theta}=\frac{r}{{y}}=\frac{\sqrt{{13}}}{{3}}={1.2019}cscθ=yr=313=1.2019

\displaystyle \sec{\theta}=\frac{r}{{x}}=\frac{\sqrt{{13}}}{ -{{2}}}=-{1.80278}secθ=xr=−213=−1.80278

\displaystyle \cot{\theta}=\frac{x}{{y}}=\frac{{-{2}}}{{3}}=-{0.6667}cotθ=yx=3−2=−0.6667

Likurg_2 [28]3 years ago
3 0

Answer:

\displaystyle \cos(\alpha+\beta)=\frac{120+8\sqrt{161}}{255}

Step-by-step explanation:

We are given the conditions:

\displaystyle \sin(\alpha)=-\frac{8}{17}\text{ and } \cos(\beta)=-\frac{8}{15}

Where α is in QIII and β is in QII and we want to find the exact value of cos(α + β).

The first ratio gives us the opposite side and the hypotenuse with respect to α . Then the adjacent side is (we can ignore negatives):

a=\sqrt{(17)^2-(8)^2}=15

The second ratio gives us the adjacent side and the hypotenuse with respect to β. Then the opposite side is:

o=\sqrt{(15)^2-(8)^2}=\sqrt{161}

Therefore, for α, ignoring negatives, the adjacent side is 15, the opposite side is 8, and the hypotenuse is 17.

And for β, ignoring negatives, the adjacent side is 8, the opposite side is √(161), and the hypotenuse is 15.

We can rewrite our expression as:

\displaystyle \cos(\alpha+\beta)=\cos(\alpha)\cos(\beta)-\sin(\alpha)\sin(\beta)

Since α is in QIII, sin(α), cos(α) < 0, and tan(α) > 0.

And since β is in QII, cos(β), tan(β) < 0, and sin(β) > 0.

Using this information, substitute:

\displaystyle \cos(\alpha+\beta)=\left(-\frac{15}{17}\right)\left(-\frac{8}{15}\right)-\left(-\frac{8}{17}\right)\left(\frac{\sqrt{161}}{15}\right)

Therefore:

\displaystyle \cos(\alpha+\beta)=\frac{120+8\sqrt{161}}{255}

You might be interested in
The graph of y=e* is transformed as shown in the graph below. Which equation represents the transformed
butalik [34]

Answer:

what are the answers

Step-by-step explanation:

okay the answer is B. y=e^x+3

7 0
2 years ago
Write the linear equation for this table.
Vedmedyk [2.9K]

Answer:

its A

Step-by-step explanation:

8 0
2 years ago
A restaurant uses 8 1/4 pounds of carrots to make 6 carrots cakes . Frank wants to use the same recipe. How many pounds of carro
monitta
1 1/2 pounds

16 ounces = 1 pound

8 1/4 pounds = 132 ounces
132 ounces/ 6 cakes = 22
22 ounces = 1 1/2 pounds
4 0
2 years ago
Read 2 more answers
URGENT PLEASE I NEED HELP AND KINDLY SHOW THE SOLUTION/S AS WELL :))
andriy [413]

Answer:

1. Steve's age is 18 and Anne's age is 8.

2. Max's age is 17 and Bert's age is 11.

3. Sury's age is 19 and Billy's age is 9.

4. The man's age is 30 and his son's age is 10.

Step-by-step explanation:

1. Let us assume that:

S = Steve's age now

A = Anne's age now

Therefore, in four years, we have:

S + 4 = (A + 4)2 - 2

S + 4 = 2A + 8 - 2

S + 4 = 2A + 6 .................. (1)

Three years ago, we have:

S - 3 = (A - 3)3

S - 3 = 3A - 9 ................................ (2)

From equation (2), we have:

S = 3A - 9 + 3

S = 3A – 6 …………. (3)

Substitute S from equation (3) into equation (1) and solve for A, we have:

3A – 6 + 4 = 2A + 6

3A – 2A = 6 + 6 – 4

A = 8

Substitute A = 8 into equation (3), we have:

S = (3 * 8) – 6

S = 24 – 6

S = 18

Therefore, Steve's age is 18 while Anne's age is 8.

2. Let us assume that:

M = Max's age now

B = Bert's age now

Therefore, five years ago, we have:

M - 5 = (B - 5)2

M - 5 = 2B - 10 .......................... (4)

A year from now, we have:

(M + 1) + (B + 1) = 30

M + 1 + B + 1 = 30

M + B + 2 = 30 .......................... (5)

From equation (5), we have:

M = 30 – 2 – B

M = 28 – B …………………… (6)

Substitute M from equation (6) into equation (4) and solve for B, we have:

28 – B – 5 = 2B – 10

28 – 5 + 10 = 2B + B

33 = 3B

B = 33 / 3

B = 11

Substituting B = 11 into equation (6), we have:

M = 28 – 11

M = 17

Therefore, Max's age is 17 while Bert's age is 11.

3. Let us assume that:

S = Sury's age now

B = Billy's age now

Therefore, now, we have:

S = B + 10 ................................ (7)

Next year, we have:

S + 1 = (B + 1)2

S + 1 = 2B + 2 .......................... (8)

Substituting S from equation (7) into equation (8) and solve for B, we have:

B + 10 + 1 = 2B + 2

10 + 1 – 2 = 2B – B

B = 9

Substituting B = 9 into equation (7), we have:

S = 9 + 10

S = 19

Therefore, Sury's age is 19 while Billy's age is 9.

4. Let us assume that:

M = The man's age now

S = His son's age now

Therefore, now, we have:

M = 3S ................................... (9)

Five years ago, we have:

M - 5 = (S - 5)5

M - 5 = 5S - 25 ................ (10)

Substituting M from equation (9) into equation (10) and solve for S, we have:

3S - 5 = 5S – 25

3S – 5S = - 25 + 5

-2S = - 20

S = -20 / -2

S = 10

Substituting S = 10 into equation (9), we have:

M = 3 * 10

M = 30

Therefore, the man's age is 30 and his son's age is 10.

5 0
3 years ago
Jacki evaluated the expression below.
Valentin [98]
Jacki didn’t subtract 12 from 8 correctly he was suppose to get a negative and not 12
3 0
3 years ago
Read 2 more answers
Other questions:
  • Don is paid $4.75 on each class ring sold. How much will he earn if he sells 90 class rings?
    13·1 answer
  • Find the area of the following shape.
    13·2 answers
  • Help<br> one who explains better will get brainliest
    6·2 answers
  • The lengths of the sides of a triangle are 3, 3, 3 square root two . Can the triangle be a right triangle? yes or no
    12·1 answer
  • What is -4.65 as a fraction?
    14·1 answer
  • PLEASE HELP ME!!!!!!!
    15·1 answer
  • Carl earned grades of 62 78 59 and 89 on four math tests what is the mean if his grades
    5·2 answers
  • As the teams fundraiser,Agnes and Betty both sold candy bars at the end of the fundraiser Agnes determined that she sold 8 more
    11·1 answer
  • Life Expectancies In a study of the life expectancy of people in a certain geographic region, the mean age at death was years an
    8·1 answer
  • A man has 14 coins in his pocket, all of which are dimes and quarters. If the total value of his
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!