Another question from O Level Additional Mathematics (A-Math).
hey. i just want to clarify something that i'm not very sure of.
is nCr x r! = nPr ??
nCr = nPr/r!
Well, I never remember this 'rule'
For example, find the number of ways to form a 3 letter word from a,b,c,d,e
Both answers are correct though different approaches are taken, so no need to remember the 'rule'