answers already passed
constant rule - correct answer ✔✔
power rule - correct answer ✔✔
constant multiple rule - correct answer ✔✔
sum + differences rule - correct answer ✔✔
product rule - correct answer ✔✔
quotient rule - correct answer ✔✔
chain rule - correct answer ✔✔
sinx - correct answer ✔✔ cosx
cosx - correct answer ✔✔ -sinx
tanx - correct answer ✔✔ sec^2x
cotx - correct answer ✔✔ -csc^2x