Question

Resolva as seguintes equações:

a) x+5/x=7/4

b) x+1/x -2=x-1/x+2

c) 5/x+2- 1/x-2=x/x²- 4

d) 3/x+ 1/x-1 = -3x+4/x ²- x

Urgente!!!

Answer 1

a) x+5/x=7/4, basta multiplicar em cruz as razões, veja:

(x+5).4 = 7.x

4.x + 20 = 7.x

20 = 7.x - 4.x

20 = 3.x

20/3 = x

x = 20/3  0u x ≅ 6,6...

b) x+1/x -2=x-1/x+2

(x+1).(x+2) = (x-2).(x-1)

x² + 3x + 2 = x² - 3x + 2  

x² + 3x + 2 - x² + 3x - 2 = 0

6x = 0

x = 0