Răspunsuri

2014-04-24T20:44:15+03:00
Imi pare rau dar nu stiu cum se rezolva, din pacate. Te-as ajuta, dar sunt in clasa a IV-a. ;)
Nu te pune nimeni sa rezolvi papusa daca nu stii inca vei invata in clasa a 8-a ;)
Cel mai inteligent răspuns!
2014-04-24T20:49:02+03:00
A)2X²-5=0⇒X²=√5/2⇒Xunu=√5/2si Xdoi=-√5/2⇒S={-√5/2, √5/2{
B)(X-1)²-4=0⇒(x-1-2)(x-1+2)=0⇒(x-3)(x+1)=0⇒
x-3=0⇒Xunu=3
x+1=0⇒x=-1
S={-1,3}
C)(6x+1)²-(x+1)²=0
6x²+12x+1-x²-2x-1=0
5x²+10x=0
5x(x+2)=0
Xunu=0
x+2=0
x=-2
S={-2, 0}
D)16x²-1=0
(4x²+1)(4x²-1)=0
4x²+1=0
x²=-1/4⇒ x=√-1/4  nu are solutii
4x²-1=0
x²=1/4
x=1/2 si x=-1/2
S={-1/2, 1/2}

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