MathMaster
Q & A
Blog
Tutorials
Calculators
Privacy policy
CONTACT US
Menu
Home
general
given cos26 k find cos13
Question
given cos26=k find cos13
Like
93
likes
465
views
Answer to a math question given cos26=k find cos13
Miles
4.9
69
Answers
cos(2θ) = 2 \times cos^2(θ) - 1
cos^2(θ) = \frac{(cos(2θ) +1)}{2}
cos^2(13) = \frac {cos(26) +1}{2}
cos^2(13) = \frac{k +1}{2}
\cos\:13\:=\pm\sqrt{\left(\frac{k+1}{2}\right)}}
Frequently asked questions (FAQs)
Math question: Find the limit as x approaches infinity of (e^x - x)/(x^2 + 2x)
+
What is the range of the sine function over the interval [0, π]?
+
What is the limit as x approaches 4 of (3x^2 - 16)/(x - 4)?
+
New questions in Mathematics
Add. 7/w²+18w+81 + 1/w²-81
QUESTION l. An investigation has been carried out in a region to know the perception of "citizen insecurity" of its inhabitants. 1,270 people in the region were interviewed, of which 27.1% responded that it was a "serious" problem. Knowing that this opinion was previously held by 25.3% of the population of that region, we want to know if said opinion has changed significantly for a confidence level of 97.2%. Taking this statement into account, the following is requested: a) Critical value of the contrast statistic. b) Solve the hypothesis test and indicate what conclusion we can reach. c) P-value of contrast.
If O(3,-2) is reflected across x = 2. What are the coordinates of O
Consider numbers from 1 to 2023. We delete 3 consecutive numbers so, that the avarage of the left numbers is a whole number
The miles per gallon (mpg) for each of 20 medium-sized cars selected from a production line during the month of March are listed below. 23.0 21.2 23.5 23.6 20.1 24.3 25.2 26.9 24.6 22.6 26.1 23.1 25.8 24.6 24.3 24.1 24.8 22.1 22.8 24.5 (a) Find the z-scores for the largest measurement. (Round your answers to two decimal places.) z =
Substitute a=2 and b=-3 and c=-4 to evaluate 2ac/(-2b^2-a)
Calculate the value of a so that the vectors (2,2,−1),(3,4,2) and(a,2,3) are coplanar.
In the telephone exchange of a certain university, calls come in at a rate of 5 every 2 minutes. Assuming a Poisson distribution, the average number of calls per second is: a) 1/8 b) 1/12 c) 1/10 d) 2/5 e) 1/24
DuocUC 2) The cost C, in pesos, for the production of x meters of a certain fabric can be calculated through the function: (x+185) C(x)=81300-6x+ 20000 a) It is known that C(90) 5.344. Interpret this result. (2 points) b) Calculate C'(x) (2 points) 3 x²+111x-0.87 20000 2000 c) Function C calculates the cost while producing a maximum of 500 meters of fabric. Determine the values of x at which the cost of production is increasing and the values of x at which the cost is decreasing. (3 points) d) If a maximum of 500 meters of fabric are produced, what is the minimum production cost? (
Use a pattern to prove that (-2)-(-3)=1
User One of the applications of the derivative of a function is its use in Physics, where a function that at every instant t associates the number s(t), this function s is called the clockwise function of the movement. By deriving the time function we obtain the velocity function at time t, denoted by v(t). A body has a time function that determines its position in meters at time t as S(t)=t.³√t+2.t . Present the speed of this body at time t = 8 s.
15.A newly married couple purchased a home with a $123710 down payment. They financed the remaining balance of the home with a mortgage. Their payments were $15395 at the end of every six months for 23 years and the interest rate was 10.6%, compounded semi-annually. How much did they purchase their home for. Enter to the nearest cent (two decimals). Do not use $ signs or commas in the answer.
2X+2=8
Pablo has a balance of $440,000 and 2/5 of the money is used to pay bills. How much money do you have left after paying the bills?
A factory produces glass for windows. The thickness X of an arbitrarily selected pane of glass is assumed to be Normally distributed with expectation μ = 4.10 and standard deviation σ = 0.04. Expectation and Standard deviation is measured in millimeters. What is the probability that an arbitrary route has a thickness less than 4.00 mm?
the product of a 2-digit number and a 3-digit number is about 50000, what are these numbers
calculate the product of 4 and 1/8
Recall that with base- ten blocks, 1 long = 10 units, 1flat = 10 long, and a block = 1 unit. Then what number does 5 flat, 17long and 5 units represent represent ?
Sarah is lining a square tray with 1 inch square tiles. the side length of the tray is 9 inches. How many tiles does Sarah need?
Construct a set of six pieces of data with mean, median, and midrange of 67 and where no two pieces of data are the same.
Download NOW
Apple store
Download NOW
Google play
Solve NOW
Try On Web
You might be interested in
Calculate to represent the function whose graph is a line that passes through the points (1,2) and (−3,4). What is your slope?
reduction method 2x-y=13 x+y=-1
The profit G of the company CHUNCHES SA is given by G(x) = 3×(40 – ×), where × is the quantity of items sold. Find the maximum profit.
(5u + 6)-(3u+2)=
2x2 and how much?
sin 30
Two business partners have a bank balance of $17,942.00. After the first year their interest brings their balance to $18,928.91. What rate of interest is earned?
Convert 5/9 to a decimal
At the dance there are 150 boys the rest are girls. If 65% are girls what is the total amount in the room
392929-9
The grading on a $159,775 house comes to $3974.75. What percent of the total cost is this? (Express your answer to the nearest hundredth percent.)
Determine the Linear function whose graph passes through the points (6, -2) and has slope 3.
We have two distributions: A (M = 66.7, 95% CI = [60.3, 67.1]) / B (M = 71.3 95% CI = [67.7, 74.9]). Erin maintains that B is significantly larger than A. Provide your opinion on Erin’s argument and justify your opinion.
a) Statistics scores are normally distributed with the mean of 75 and standard deviation of 7. What is the probability that a student scores between 80 and 88
Let G be the center of gravity of triangle ABC. We draw through A a parallel to BC on which we take a point D so that DG⊥BG. If the area of the quadrilateral AGBD is equal to s, show that AC·BD≥2·s.
If the mean of the following numbers is 17, find the c value. Produce an algebraic solution. Guess and check is unacceptable. 12, 18, 21, c, 13
A 20-year old hopes to retire by age 65. To help with future expenses, they invest $6 500 today at an interest rate of 6.4% compounded annually. At age 65, what is the difference between the exact accumulated value and the approximate accumulated value (using the Rule of 72)?
Determine the general solution of the equation y′+y=e−x .
It costs a manufacturer $2,500 to purchase the tools to manufacture a certain homemade item. If the cost for materials and labor is 60¢ per item produced, and if the manufacturer can sell each item for 90¢, find how many items must he produce and sell to make a profit of $2000?
Write a linear equation in the slope-intercept form. Slope of the line is -1 and goes through (8,4)