lanay645
05.05.2020 •
Mathematics
Find cos(2* angle ABC) 100 POINTS
Solved
Show answers
More tips
- F Food and Cooking How many stages of coffee roasting are there?...
- G Goods and services Kogda zhdatt Iphone 5? The Latest News and Rumors...
- F Family and Home Parquet or laminate, which is better?...
- L Leisure and Entertainment How to Properly Wind Fishing Line onto a Reel?...
- L Leisure and Entertainment How to Make a Paper Boat in Simple Steps...
- T Travel and tourism Maldives Adventures: What is the Best Season to Visit the Luxurious Beaches?...
- H Health and Medicine Kinesiology: What is it and How Does it Work?...
- O Other How to Choose the Best Answer to Your Question on The Grand Question ?...
- L Leisure and Entertainment History of International Women s Day: When Did the Celebration of March 8th Begin?...
- S Style and Beauty Intimate Haircut: The Reasons, Popularity, and Risks...
Answers on questions: Mathematics
- M Mathematics 12 K12.com My Info K12 Customer Sup. Class Connect LogMeln123 Microsoft Office 365 KB KBH 12 K12 Online School Back to Content 3.16 Unit Test: Slope - Part 1 This graph shows the...
- M Mathematics Which equation has only one solution? |x – 5| = –1 |–6 – 2x| = 8 |5x + 10| = 10 |–6x + 3| = 0...
- M Mathematics How does deposition explain the layers that are often found in sedimentary rock?...
- M Mathematics Jennifer works in a flower shop on saturday she started work at 8: 45 a.m. she spent 3/4 hours at lunch she finished at 4: 15 p.m. how many hours did she work on saturday?...
- M Mathematics What is the solution to the system of equations 2x-5y=-5 and x+2y=11?...
- M Mathematics Cory biked 48 miles in 3 hours. at this rate, how far could he bike in 5 hours? a. 50 mi b. 53 mi c. 80 mi d. 240 mi...
- M Mathematics Which one of the following statements is true about parallel lines...
- M Mathematics The amount of money the athletic booster club raised for the year is modeled by the function f(x) = 250x + 750. how much money did the booster club have at the start? a) the booster...
- M Mathematics What is the slope of the line? y = 5 + 4x question 5 options: a) 5 b) 9 c) 1 d) 4...
- M Mathematics Lmn≅pqr what is the value of x in degrees? enter your answer in the box. x = °...
Ответ:
3/5
Step-by-step explanation:
We need to use the trig identity that cos(2A) = cos²A - sin²A, where A is an angle. In this case, A is ∠ABC. Essentially, we want to find cos∠ABC and sin∠ABC to solve this problem.
Cosine is adjacent ÷ hypotenuse. Here, the adjacent side of ∠ABC is side BC, which is 4 units. The hypotenuse is 2√5. So, cos∠ABC = 4/2√5 = 2/√5.
Sine is opposite ÷ hypotenuse. Here, the opposite side of ∠ABC is side AC, which is 2 units. The hypotenuse is still 2√5. So sin∠ABC = 2/2√5 = 1/√5.
Now, cos²∠ABC = (cos∠ABC)² = (2/√5)² = 4/5.
sin²∠ABC = (sin∠ABC)² = (1/√5)² = 1/5
Then cos(2∠ABC) = 4/5 - 1/5 = 3/5.
Ответ:
⅗ or 0.6
Step-by-step explanation:
According to the double angle identity:
cos(2X) = 2cos²(X) - 1
Let Angle ABC = X, then
cos(X) = 4/[2sqrt(5)]
cos²(X) = 4²/[2sqrt(5)]²
= 16/20
= 4/5
cos(2X) = 2(4/5) - 1 = 3/5
Ответ:
sorry idk
step-by-step explanation: