中二數學Change of Subject [複製鏈接]

1. Make s the subjecct of the formula

    1/r  =  ax / x-1 + 1/s

2. Make x the subjecct of the formula

    1/r  =  ax / x-1 + 1/s (同上的)

希望可以連步驟，唔該各位
我明天要交功課的:o

1. Make s the subject of the formula

    1/r  =  ax / x-1 + 1/s
    1/s =  1/r - ax / x-1
           =  (x - 1 - axr) / r (x - 1)
        s = r ( x-1) / (x - 1 -axr )

2. Make x the subject of the formula

    1/r  =  ax / x-1 + 1/s (同上的)
     1 / r - 1 / s = ax / x - 1
     ( s -  r ) / rs = ax / x - 1
      ( s - r )( x - 1 ) = axrs
      sx - rx - s + r = axrs
     axrs - sx + rx = r - s
      x ( ars - s + r) = r - s
      x = ( r - s ) / (ars - s + r )
  

1. Make s the subjecct of the formula

    1/r  =  ax / x-1 + 1/s
1/r-ax/x-1=1/s
(x-1)/r(x-1)-axr/(x-1)(r)=1/s
x-1-axr/r(x-1)=1/s
s(x-1-axr)=r(x-1)
S=r(ax-1)(x-1-axr)

2. Make x the subjecct of the formula

    1/r  =  ax / x-1 + 1/s (同上的)
做法一樣..