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
Alexxx [7]
3 years ago
13

For positive acute angles A and B, it is know that tan A= 8/15 and sin B= 11/61. Find the value of cos (a+b) in simplest form

Mathematics
1 answer:
iragen [17]3 years ago
7 0

Answer:

812/1037

Step-by-step explanation:

To solve this, we have to use trigonometric identities.

Cos (A + B) is given as Cos A Cos B - Sin A Sin B. And from the question, we have that

Tan A = 8/15.

We know that in a triangle, the Tan angle is represented Opp/Adj and thus the Opp is 8, and the Adj is 15. Using Pythagoras, we have

hyp² = opp² + adj²

hyp² = 8² + 15²

hyp² = 64 + 225

hyp² = 289

hyp = √289 = 17

The identity of Cos is Adj/Hyp and that of Sin is Opp/Hyp.

Cos A = 15/17

Sin A = 8/17

Repeating the same process for B, we have

Sin B = 11/61

adj² = hyp² - opp²

adj² = 61² - 11²

adj² = 3721 - 121

adj² = 3600

adj = √3600 = 60

Cos B = 60/61

Now, using the earlier stated trigonometric identity, we have

cos (a + b) = CosA CosB - SinA SinB

cos (a + b) = 15/17 * 60/61 - 8/17 * 11/61

cos (a + b) = 900/1037 - 88/1037

cos (a + b) = 812/1037

You might be interested in
The sum of two numbers is 57. The smaller number is 19 less than the larger number. What are the numbers?
Rufina [12.5K]
The numbers are 38 and 19
6 0
3 years ago
Read 2 more answers
Write 7*10*10*10*10 with an exponent<br> 7*10*10*10*10=
MAVERICK [17]
7x10^4

Because there are 4 sets of 10
5 0
3 years ago
Read 2 more answers
PLEASE HELP! I WILL GIVE BRAINLIEST!<br> A<br> B<br> C<br> D<br> E
I am Lyosha [343]

Answer:

D

Step-by-step explanation:

6 0
3 years ago
Read 2 more answers
What is the classification for this polynomial 2u^2vw^2
Alexxx [7]
It’s a monomial for sure
6 0
4 years ago
Read 2 more answers
The probability of passing the math class of Professor Jones is 64%, the probability of passing Professor Smith's physics class
alexgriva [62]

Answer:

The probability of using one or the other is 36%

Step-by-step explanation:

For solving this problem it is easy if we see it in a ven diagram, for this first we are going to name the initial conditions with some variables:

Probability of passing Professor Jones math class = 64% =0,64

P(J) = 0.64

Probabiliry of passing Professor Smith's physics class = 32% =0.32

P(S) = 0.32

Probability of passing both is = 30% = 0.30

P(JnS) = 0.30 (Is is an intersection so it is in the middle of the ven diagram

We need to know which is the probability of pasing one or the other for this we need to take out the probability of passing both for this we have to add the probability of passing  Professor Jones math class with the probabiliry of passing Professor Smith's physics class and substract the probability of passing both for each one:

P(JuS) = (P(J) - P(JnS)) + (P(S) - P(JnS)) = (0.64 - 0.30) + (0.32 - 0.30) = 0.34 + 0.02 = 0.36 = 36%

If you check the ven diagram you can see that if we add all what is in red we will have the probability of passing Professor Jones math class and if we add all what is in blue we wiill have the probability of passing Professor Smith's physics class, and if we add just what is in each corner we will get the same value that is the probabilty of passsing one or the other.

5 0
3 years ago
Other questions:
  • Guys help mee please with subject of the formula <br>these 2 questions ​
    7·1 answer
  • Daniel needs to sell candy bars For a club fundraiser. She starts with 72 candy bars and begin selling at a constant rate of eig
    9·1 answer
  • the system ax+by=c has the solution (2,-3), where dx+ey=f a, b, c, d, e, and f are non-zero real numbers. select all the systems
    13·2 answers
  • What is the value of f(x) when x = -3? <br> f(x)= -2x-3 <br> f(-3)=???
    7·2 answers
  • a student government organization is selling christmas trees as a fundraiser. on friday, they sold five noble fir trees and thre
    12·1 answer
  • Part a: identity a fraction equivalent to 15/60. show all work.
    7·2 answers
  • Find the perimeter and area of following rectangle
    10·1 answer
  • Please answer and explain I’ll mark brainliest!!!!!
    7·1 answer
  • I need help on both of the question
    6·1 answer
  • F
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!