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
WINSTONCH [101]
3 years ago
8

PLEASE HELP ME!!! I don’t understand

Mathematics
2 answers:
s344n2d4d5 [400]3 years ago
8 0

Answer:

see explanation

Step-by-step explanation:

Using the addition formula for cosine

cos(x ± y) = cosxcosy ∓ sinxsiny

and exact values

sin45° = cos45° = \frac{\sqrt{2} }{2}

c0s30° = \frac{\sqrt{3} }{2} , sin30° = \frac{1}{2}

Express cos15° = cos(45 - 30 )°, then

cos(45 - 30)°

= cos45°cos30° + sin45°sin30°

= \frac{\sqrt{2} }{2} × \frac{\sqrt{3} }{2} + ( \frac{\sqrt{2} }{2} × \frac{1}{2} )

= \frac{\sqrt{6} }{4} + \frac{\sqrt{2} }{4}

= \frac{\sqrt{6}+\sqrt{2}  }{4} ← exact value

ElenaW [278]3 years ago
6 0

Answer:

   √6 + √2

= --------------

        4

Step-by-step explanation:

15° = 45° - 30°

So

cos(15)  = cos(45 - 30)

=cos(45)  × cos(30) + sin(45) × sin(30)

= 1/√2  × (√3)/2  + 1/√2 × 1/2

    (√3) + 1

= --------------

     2√2

    (√3) + 1              √2

= -------------- x       ---------

     2√2                  √2

   √6 + √2

= --------------

        4

You might be interested in
HELP PLZ BRAINIEST TO WHOEVER RIGHT
ch4aika [34]

Answer:

five-number summary

Step-by-step explanation:

3 0
3 years ago
I NEED HELP I'M IN TIMER:
alekssr [168]

1/2x - 7 = 1 5/10

I'd go with c.

8 0
3 years ago
Read 2 more answers
Find the slope using points ( 5.1) and (9,4)
koban [17]

Answer:

Step-by-step explanation:

m = (4-1) / (9-5)

m = 3/4

5 0
3 years ago
for a project in her geometry class, amira uses a mirror on the ground to measure the height of her school’s football goalpost.
kari74 [83]

Answer:

6.14 m

Step-by-step explanation:

8 0
3 years ago
Find the exponential function that contains the points (0,5) and (2,20)
amid [387]
Do it open the link takes all your information have a good one
3 0
3 years ago
Other questions:
  • How do I know when to use addition or subtraction when doing compound event probability?
    12·1 answer
  • 200 is 25% of what number
    7·1 answer
  • A cd/mp3 player for a car cost 170 dollars it is on sale for 12% off with a free installation
    8·1 answer
  • Peter has 96 stamps and Sam has 63. How many stamps should Sam give Peter so that Peter will have twice as many stamps as Sam?
    13·2 answers
  • Which is the graph of f(x) = square root 4x
    10·1 answer
  • there are 30 cities in a country. Each city has 4 highways coming out of it. How many highways connecting 2 cities are there in
    6·1 answer
  • Is 700 yards bigger then 2000 feet?
    10·2 answers
  • A farm lets you pick 3 pints of raspberries for $12.00. What is the cost per pint? How many pints do you get per dollar? At this
    15·2 answers
  • PLS HELP BRAINLIEST<br><br> pls pls pls
    9·1 answer
  • FIND THE PRODUCTS OR QUOTIENYS IN THE EXPONENTIAL FORMS BY USING LAWS OF INDICES.​
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!