need help with calculating combinations and permutations

[silly]

I'm stuck on working through these, no idea on how to get to the answer.

ⁿC_n-2

and

ⁿP_n-2

 

[stapel]

I'm stuck on working through these, no idea on how to get to the answer.

ⁿC_n-2

and

ⁿP_n-2

You plugged the given values into the given formulas, and... then what?

Please be complete. Thank you!

 

[Dr.Peterson]

I'm stuck on working through these, no idea on how to get to the answer.

ⁿC_n-2

and

ⁿP_n-2

I hope you recognize that the answers will not be numbers, but expressions, and not even necessarily closed-form expressions.

As suggested, start by using the formulas you have (presumably) been given, and then see if you can simplify.