To verify the identity tan(x1+x2+x3)= tanx1+tanx2+tanx3-tanx1tanx2tanx3/1 -tanx1tanx2-tanx2tanx3-tanx1tanx3, what should you do first?

Could someone with number 1 and 2

Which of the following parabolas opens down?

Which of the following best describes the graph below? + + 2 + 3 + 4 1 o a. it is not a function. o b. it is a one-to-one function. o c. it is a many-to-one function. o d. it is a function, but it is not one-to-one.