If tana tanb=k, show that(1+k)cos(a+b)=(1-k)cos(a-b)

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

How does the graph of g(x)=⌊x⌋−3 differ from the graph of f(x)=⌊x⌋? the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted right 3 units. the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted up 3 units. the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted down 3 units. the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted left 3 units.

At the "no mutants allowed" country farm, every sheep has 4 legs, every chicken has two legs, and all animals have only 1 head. asked to count how many sheep and chicken are in the fields, a farm boy reports back that there are 140 feet and 50 heads. how many sheep and chicken are there? there are sheep and chicken at the farm.