Prove that 1-cos2A/sin 2A=tanA

When drawing a trend line for a series of data on a scatter plot, which of the following is true? a. there should be an equal number of data points on either side of the trend line. b. all the data points should lie on one side of the trend line. c. the trend line should not intersect any data point on the plot. d. the trend line must connect each data point on the plot.

Julia is going for a walk through the neighborhood. what unit of measure is most appropriate to describe the distance she walks?

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?