ƚ@"@ u  .  @ @"&" & MathType Symbol ؟ww w f-2 5(ySymbol ؟ww w f-2 @)ySymbol ؟ww w f-2 (ySymbol ؟ww w f-2 W )ySymbol ؟ww w f-2 (ySymbol ؟ww w f-2 )ySymbol ؟ww w f-2 (ySymbol ؟ww w f-2 !)y-Times New Roman؟ww w f-2 27 2   2 L 2  7 2   2  2  2 @ 2 "272 l972 37 2  2  2  2  2 @ 2 |9 2 3 2   2  2  2 @ 2  9 2 E3 2 ?3 2 9 2 3 2  9 2 3 2 3  Times New Roman؟ww w f-2 F6 2 2 2 i4 2 d#2 2 ds4 2 d6 2 2 2 <4 2 2 2 4 2 %2 2 2 2 4 2 }2 Symbol ؟ww w f-2 - 2  = 2 - 2 X- 2 - 2 b+ 2 + 2  = 2 + 2 ++ 2 +- 2 + 2 + 2  = 2 q + 2 + 2 l- Times New Roman؟ww w f-2 x 2 Dx 2 x 2 Tx 2 x 2 x 2 x 2 mx 2 x 2 Fx 2 Vx 2 x 2 x 2 x & "Systemҩ f !-