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
Alborosie
3 years ago
7

If cos (A+B) = cosAcos B – sinAsin B , find the value of cos 75

Mathematics
1 answer:
kirill [66]3 years ago
4 0

Answer:

Step-by-step explanation:

Cos 75 = Cos ( 30 + 45)  {Use Cos (A + B) identity}

            = Cos 30*cos 45 - Sin 30 Sin 45

            = \frac{\sqrt{3}}{2}*\frac{1}{\sqrt{2}}-\frac{1}{2}*\frac{1}{\sqrt{2}}\\\\= \frac{\sqrt{3}}{2\sqrt{2}}-\frac{1}{2\sqrt{2}}\\\\=\frac{\sqrt{3}-1}{2\sqrt{2}}\\\\=\frac{(\sqrt{3}-1)*\sqrt{2}}{2\sqrt{2}*\sqrt{2}}\\\\=\frac{\sqrt{3}*\sqrt{2}-\sqrt{2}}{2*2}\\\\=\frac{\sqrt{6}-\sqrt{2}}{4}

You might be interested in
The price of a visit to the dentist is \$50$50. If the dentist fills any cavities, an additional charge of \$100$100 per cavity
kenny6666 [7]

Answer:300

Step-by-step explanation:

um i dk know if the two 50$ means any thing but thats what i got

7 0
3 years ago
22<br> 1 point<br> If f (x) = 7– 41, what is f (-10)?
Anettt [7]

Answer:

f(x)+41 f(-10)=7

Step-by-step explanation:

5 0
3 years ago
Write a decimal that is 1/10 of .9
amm1812
1/10 of .9 is the same as dividing .9 by 10. .90 / 10 = .09 .09 is the answer
8 0
3 years ago
Consider the limaçon with equation r = 3 4cos(θ). how does the quotient of a and b relate to the existence of an inner loop?
Delicious77 [7]

If the equation is r = 3 +4cos(θ) then because b/a>1 the curve is a limacon with an inner loop.

Given limacon with equation r=3+4cos(θ) and we have to answer how the quotient of a and b relate to the existence of an inner loop.

Equation is like a relationship between two or more variables expressed in equal to form and it is solved to find the value of variables.

formula of polar graph is similar to r= a+ b cos (θ).

Case 1. If a<b or b/a>1

then the curve is a limacon with inner loop.

Case 2. If a>b or b/a<1

Then the limacon does not have an inner loop.

Here given that r=3+4cos (θ)

It is observed that , a<b or b/a>1

Therefore the curve is limacon with an inner loop.

Hence because b/a>1 the curve is a limacon with an inner loop.

Learn more about limacon at brainly.com/question/14322218

#SPJ4

5 0
2 years ago
One number is 3 less than twice another. If their sum is 39 find the numbers
DedPeter [7]

Answer:

The numbers are 14 and 25

Step-by-step explanation:

Let one of the numbers be x. The second number we are told is 3 less than twice x. The second number will thus be;

2x - 3

The sum of the numbers is thus;

x + (2x - 3) = 3x - 3

But the sum of the numbers is said to be 39, therefore;

3x - 3 = 39

3x = 42

x = 14

The second number is thus;

2(14) - 3 = 28 - 3 = 25

5 0
3 years ago
Other questions:
  • Finals are​ over, and you are moving back home for the summer. You need to rent a truck to move your possessions from the colleg
    6·1 answer
  • How many tens is in 3980
    13·1 answer
  • Find all solutions to each quadratic equation
    10·1 answer
  • 13<br> Simplify the following expression.<br> -84 = 12<br> O<br> A.<br> 7<br> oc.<br> o D. 8<br> o v
    10·1 answer
  • 3 tenths + 4 Tenths = __0.7____ tenths
    9·1 answer
  • Complete the square for x2 - 4x +<br> Then write the resulting expression as a<br> binomial squared.
    12·1 answer
  • Someone help me on Theese 2
    6·1 answer
  • If x^2 + 1/x^2 = 18 , find the value of x^3-1/x^3​
    14·2 answers
  • What is the sum of the two expressions? (3/7x+4)+(1/7x-2)
    5·1 answer
  • What is the volume of this triangular pyramid?<br> 9 cm<br> 7 cm<br> 8 cm
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!