Find all degree solutions. 2cos^2 2theta-cos2theta-1=0

Which of the following is the true for f(x) = 5cos

Seattle, washington is known for being rainy. one day last month, 8 inches of rain fell in 1 1/2 hours. what us the rate of the rainfall expressed in ft per plzzz write a proportion i will give you 100 points

An arithmetic series a consists of consecutive integers that are multiples of 4 what is the sum of the first 9 terms of this sequence if the first term is 0