Question

1)Rezultatul calculului:
$\sqrt{2} \times \frac{5}{ \sqrt{2} } - 1$

2)Descompuneti:
${x}^{3} - 3x$

3)Daca
$x + \frac{1}{x} = 3$
atunci
${x}^{2} + \frac{1}{ {x}^{2} } =$
dupa egal este semnul intrebari (?)

4)Daca
$x = (7 + \sqrt[2]{11} )(8 - \sqrt{19} ) \\ y = (8 + \sqrt{19} )(7 - \sqrt[2]{11} )$
media geometrica=? (mg=?)

VA ROG FRUMOS AM NEVOIE PENTRU MAINE !DAU COROANA !

Answer 1

1) rad 2 x 5/rad 2 -1 = 5 - 1 = 4

2) x^3 - 3x = x(x^2-3)

3) x+1/x = 3
   Atunci (x+1/x)^2 = x^2 + 2*x*1/x + 1/x^2 = x^2 + 1/x^2 + 2 = 3
   x^2 + 1/x^2 = 3-2 = 1

4) x = (7+rad11)(8-rad19)
    y = (8+rad19)(7-rad11)
  Mg = rad [(7+rad11)(8-rad19)(8+rad19)(7-rad11)] = rad[(7+rad11)(7-rad11)(8+rad19)(8-rad19)] = rad[(49-11)(64-19)] = rad(38*45) = rad(2*3^2*5*19) = = 3rad190