How many ways are there to distribute n distinct balls into r boxes (a box can contain any number of balls, ranging from zero (none) all the way to all n balls)?

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

The median am of triangle ∆abc is half the length of the side towards which it is drawn, bc . prove that triangle ∆abc is a right triangle, and find angle mac and abm

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)