resolva as equações fracionárias abaixo:a) 1/x-3 +2 = 3/x-3b) 4/x+2-6/x-2=-2-5x/x²-4c) 5/x-3-2/x+3=x²-9
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a) 1/(x-3 + 2 = 3/(x-3)
1 + 2(x-3) = 3
-- ------- ---
x-3 x-3 x-3
1 + 2x - 6 = 3
------------ -----
x-3 x-3
2x -5 = 3
------ -----
x-3 x-3
(2x - 5)(x-3 ) = 3 ( x-3)
2x² - 6x - 5x + 15 = 3x -9
2x² - 14x + 24
x² -7x + 12
b) 4/(x+2) - 6/(x-2) = -2-5x/(x+2)(x-2)
4 ( x-2) - 6(x+2) = -2 - 5x
--------- -------- ---------
(x+2)(x-2) (x+2)(x-2) (x+2)(x-2)
4x -8 -6x - 12 = -2 - 5x
----------------- ----------
(x+2)(x-2) (x+2)(x-2)
-2x - 20 + 2 + 5x =
------------------------
(x+2) (x-2)
-7x -18
-----------
x² - 4
c) 5/(x-3) - 2/(x+3) = x² - 9
5(x+3) - 2(x-3) = (x+3) (x-3)
------- -------- --------------
(x+3)(x-3) (x+3)(x-3) (x+3)(x-3)
5x + 15 - 2x + 16 = 1
--------------------- ---
x² - 9
x² - 9 = 3x + 21
x² -3x - 21 - 9
x² -3x - 30
1 + 2(x-3) = 3
-- ------- ---
x-3 x-3 x-3
1 + 2x - 6 = 3
------------ -----
x-3 x-3
2x -5 = 3
------ -----
x-3 x-3
(2x - 5)(x-3 ) = 3 ( x-3)
2x² - 6x - 5x + 15 = 3x -9
2x² - 14x + 24
x² -7x + 12
b) 4/(x+2) - 6/(x-2) = -2-5x/(x+2)(x-2)
4 ( x-2) - 6(x+2) = -2 - 5x
--------- -------- ---------
(x+2)(x-2) (x+2)(x-2) (x+2)(x-2)
4x -8 -6x - 12 = -2 - 5x
----------------- ----------
(x+2)(x-2) (x+2)(x-2)
-2x - 20 + 2 + 5x =
------------------------
(x+2) (x-2)
-7x -18
-----------
x² - 4
c) 5/(x-3) - 2/(x+3) = x² - 9
5(x+3) - 2(x-3) = (x+3) (x-3)
------- -------- --------------
(x+3)(x-3) (x+3)(x-3) (x+3)(x-3)
5x + 15 - 2x + 16 = 1
--------------------- ---
x² - 9
x² - 9 = 3x + 21
x² -3x - 21 - 9
x² -3x - 30
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