show that sin^4x=(3/8)-.5cos2x+(1/8)cos4x

The owner of a computer repair shop had determined that their daily revenue has been mean $7200 and standard deviation $1200. The daily revenue totals for next 30 days will be monitored. What is the probability that the mean daily revenue for the next 30 days will exceed $7500?

92. Dental services. The national cost C in billions of dollars for dental services can be modeled by the linear equation C _ 2.85n _ 30.52, where n is the number of years since 1990 (Health Care Financing Administration, www.hcfa.gov). a) Find and interpret the C-intercept for the line. b)...

The mass of Earth is about 6 x 1021 metric tons. The mass of the sun is about 1.998 x 1027 metric tons. About how many times the mass of Earth is the mass of the sun? Express the answer in scientific notation.

An unprepared student makes random guesses for the ten true-false questions on a quiz. Find the probability that there is at least one correct answer.

232/.73

i've got a linear algebra question... The following augmented matric is in reduced row echelon form. Find the solution set to the linear system. Here's the augmented matrix: 1 5 -2 0 | 3 0 0 0 1 | 6 0 0 0 0 | 0 0 0 0 0 | 0

Use the information you gathered throughout the course to distinguish what you think is the greatest strength and the greatest weakness of the current special educational system in America. Write a 200- to 300-word reflection that explains your opinion.

If f(x) = 3x2 + 2x 7 represents the attitude score f(x) for a person x years old, find and interpret f(30)

9. A random sample of 48 days taken at a large hospital shows that an average of 38 patients were treated in the emergency room (ER) per day. The standard deviation of the population is 4. a. Find the 99% confidence interval of the mean number of ER patients treated each day at the...