A求P、P求A (1+i) F=P(1+i) P(1+i)=A (1+)-1 P= A A(P/A2,%,N) i(1+) (1+) P(A/P,i%, N) (1+i)-1 Do You Understand LRM? Yes, we DO! 1212 A求P、P求A (1 )N F P i = + (1 ) 1 N i F A i   + − =     (1 ) 1 (1 ) N N i P i A i   + −  + =     (1 ) 1 ( / , %, ) (1 ) N N i P A A P A i N i i   + − = =     + (1 ) ( / , %, ) (1 ) 1 N N i i A P P A P i N i   + = =     + −