a) x/x-2y + x/x + 2y + 4xy/4y²-x² b) 1/3x-2 – 1/3x+2 – 3x-6/4-9x² c) x²-36/2x+10.3/6-x

0 bình luận về “a) x/x-2y + x/x + 2y + 4xy/4y²-x² b) 1/3x-2 – 1/3x+2 – 3x-6/4-9x² c) x²-36/2x+10.3/6-x”

1. `a) x/(x-2y) + x/(x + 2y) + (4xy)/(4y²-x²)`

   `=x/(x-2y) + x/(x + 2y) – (4xy)/(x²-4y²)`

   `= (x(x+2y))/(x²-4y²) + (x(x-2y))/(x² + 4y²) – (4xy)/(x²-4y²)`

   `=(x²+2xy+x²-2y-4xy)/((x+2y).(x-2y))`

   `=(2x²-4xy)/((x+2y).(x-2y))`

   `=(2x(x-2y))/((x+2y).(x-2y))`

   `=(2x)/(x+2y)`

   `b) 1/(3x-2) – 1/(3x+2) – (3x-6)/(4-9x²)`

   `= 1/(3x-2) – 1/(3x+2) + (3x-6)/(9x²-4)`

   `= (3x+2)/(9x²-4) – (3x-2)/(9x²-4) + (3x-6)/(9x²-4)`

   `= (3x+2-3x+2+3x-6)/((3x-2).(3x+2)) `

   `= (3x-2)/((3x-2).(3x+2)) `

   `= 1/(3x+2) `

   `c) (x²-36)/(2x+10).(3)/(6-x)`

   `= ((x-6).(x+6))/(2x+10).(-3)/(x-6)`

   `= (-3(x+6))/(2x+10)`

   `= (-3x-18)/(2x+10)`

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