Question

Buna. Cine ma ajuta? : a) radical din x la a 2-a minus 4 + radical din x plus2 = 0
b) radical de ordinul 3 din x la a treia plus x la a doua minus x minus 2 = x
c)2 la puterea 2x la adoua(doar 2x) plus 3x minus 2 =8
Va roooog.

Answer 1

b) x+x la a 2 - x - 2 - x = 0
x la a 2 - x - 2 = 0 - ecuatie de gradul 2
delta = b la a patra - 4*a*c = 1 + 4*2 = 9
x1 = (-b- radical din delta)/2a = (1 - 3)/2= - 2/2 = - 1
x2= (-b+radical din delta)/2a = (1+3)/2 = 4/2 = 2
S = {- 1, 2}

Answer 2

a) √(x²-4)+√(x+2)=0
√(x²-4)=-√(x+2)
(√(x²-4))²=(-√(x+2))²
x²-4=x+2
x²-x-4-2=0
x²-x-6=0
Δ=1+24=25
x1=(1-5)/2=-4/2=-2
x2=(1+5)/2=6/2=3
S={-2,3}

b)∛(x³+x²-x-2)=x
(∛(x³+x²-x-2))³=x³
x³+x²-x-2=x²
x²-x+x²-x-2=0
x-x-2=0
Δ=1+8=9
x1=(1-3)/2=-2/2=-1
x2=(1+3)/2=4/2=2
S={-1,2}

c)nu am inteles ce ai scris