Răspunsuri

2014-01-27T15:21:13+02:00
1.  (\sqrt[3]{3x+2})^{3} = 2^{3} => 3x+2=8 =>3x=6/:3=> x=2
2. \sqrt{x-2} =4-x=>  (\sqrt{x-2})^{2} = (4-x)^{2} => x-2=16-8x+ x^{2} => x^{2} -9x+18
Δ= b^{2} -4ac=81-72=9
 x_{1,2} = \frac{-b+- \sqrt{delta} }{2a} => x_{1,2} = \frac{9+-3}{2} => \left \{ {{ x_{1} =6} \atop { x_{2} =2}} \right.
3.Cred ca ai gresit, aia nu e ecuatie.
4.  2^{x} +2^{x+1} = 3* 2^{2} => x+x+1=2=> 2x=1=> x= \frac{1}{2}
5. 3^{2x} + 3^{x} =3* 2^{2} => 2x+x=1=> 3x=1=> x= \frac{1}{3}
6. 2x-1= 5^{2} => 2x=26=> x=13
7.  \frac{x}{x+2} =8=> x=8x+16=> x=- \frac{16}{7}
8. \frac{x+1}{x-1} =3=>x+1=3x-3=> -2x=-4=>x=2
multumee multtt !! :*
Cu placere! Le fac si pe restu' acum.