Round the fraction to the nearest whole number. 3 1/2

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

What is the range of the function? f(x)=-2|x+1|? a. all real numbers. b. all real numbers less than or equal to 0. c. all real numbers less than or equal to 1. d. all real numbers greater than or equal to 1

Can somebody 1. what is the formula for finding the vertical distance between two points on a coordinate plane?