Use the fundamental identities to fully simplify the expression
3sin^3 x * csc x + cos^2 x + 2 cos(-x) * cos x

i simplified it until this
3sin^2 x + cos^2 x +2cos^2(-x)*cos(x)

i know the answer is suppose to be 3 but i don't know how to simplify further to get to 3

Which is a reasonable estimate of the amount of water in a small, inflatable pool used by children?

What is the solution to the equation? k/6.4=8.7 2.3 5.568 15.1 55.68

Aschool allots ? 1500 to spend on a trip to the theatre. theatre tickets have a regular cost of ? 55 each and are on offer for 1 5 off. a train ticket for the day will cost ? 12 each. if 2 teachers and the maximum number of students attend, how much money will the school have left over?