$MathMaster logo$

MathMaster

Home
general
given cos26 k find cos13

Question

given cos26=k find cos13

93

likes

465 views

Answer to a math question given cos26=k find cos13

$Expert avatar$

4.9

114 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)

What is the sum of the interior angles of an isosceles triangle with one angle measuring 50 degrees?

+

Math question: What is the integral of the standard formula ∫(cos(x)^2)dx? (

+

Question: What is the value of (2^3)^2 - √144 + 5^2?

+

New questions in Mathematics

Using a remarkable product you must factor the expression: f(x) =36x^2-324 and you are entitled to 5 steps

The gross domestic product the gdp for the United States in 2017 was approximately $2.05x10^3. If you wrote this number in standard notation , it would be 205 followed by how many zeros

(5u + 6)-(3u+2)=

Solve this mathematical problem if 3/5 of a roll of tape measures 2m. How long is the complete roll?

Find the derivatives for y=X+1/X-1

78 percent to a decimal

The durability of a tire of a certain brand is a Normal random variable with an average of 64,000 km and a standard deviation of 9,000 km. Assuming independence between tires, what is the probability that the 4 tires on a car will last more than 58,000 km?

A test has 5 multiple choice questions. Each question has 4 alternatives, only one of which is correct. A student who did not study for the test randomly chooses one alternative for each question.(a) What is the probability of him getting a zero on the test?(b) What is the probability of him getting a three or more? The maximum mark for the test is 5, with each question worth one point.

calculate the area in square units of A rectangle with length 6cm and breadth 5cm

Use the power rule for logarithms to solve the following word problem exactly. If you invest $1, 000 at 5% interest compounded annually, how many years will it take before you have $2,000?

Find the minimum value of the function y = -4 x3 + 60 x2 -252 x + 8 for values of x between x = 0 and x = 9 Enter the value of the function, not the value of x

MAKING AN ARGUMENT You use synthetic division to divide f(x) by (x − a) and find that the remainder equals 15. Your friend concludes that f (15) = a. Is your friend correct? Explain your reasoning.

ind the z-score for which 72% of the distribution's area lies between -z and z. -1.7417, 1.7417 -1.1538, 1.1538 -1.0803, 1.0803 -2.826, 2.826

Given a circle 𝑘(𝑆; 𝑟 = 4 𝑐𝑚) and a line |𝐴𝐵| = 2 𝑐𝑚. Determine and construct the set of all centers of circles that touch circle 𝑘 and have radius 𝑟 = |𝐴𝐵|

What is the percentage of nitrogen abundance in copper dinatrate Cu(NO3)2

did an analysis of dropout from the nursing faculty at the Universidad Veracruzana. With a poblation of 122 students, it turned out that according to the gender data, the female sex predominates with 82%, and the male sex male is found with 12%. The main factors why students drop out are, first of all, "Not "re-enrolled" at 49%, second place "Personal reasons" at 20%, third place "change of school" in 11%, "lack of documents" and "economic reasons" in 7%, change of residence and lack of social service in 3%. Of this sample, how many students dropped out for other reasons?

the length of the fenced in area is to be 5 ft greater than the width and the total amount of fencing to be used is 89 ft find the width and length

12[4 + (8 + 7) + 5]