Question

Rezolvati in R ecuatia: (Puteti rezolva si jumatate)
3√37 x^2=0
(x+3,1)*(x-7)=0
x^2+2,8x=0
-x^2+49=0
2x^2+32=0
6x^2+11x-7=0
3x^2+4x+5=0
4x^2-12x+9=0
Si la fel:
x^2-2|x|-3=0
x^4-10x^2-75=0
Va rog, sunt exercitiile de la un test si am nevoie!

Answer 1

3√37 x^2=0
x₁=x₂=0

(x+3,1)·(x-7)=0
x²-7x+3,1x-21,7=0
x²-3,9x-21,7=0
Δ=b²-4ac
Δ=(3,9)²-4·1·(-21,7)=15,21+86,8=102,01
x₁=(3,9-10,1)/2=-6,2/2=-3,1
x₂=(3,9+10,1)/2=14/2=7

x^2+2,8x=0
x(x+2,8)=0
x₁=0
x₂=-2,8

-x^2+49=0
-x²=-49      (-1)
x²=49
x₁=√49=7
x₂=-7

2x^2+32=0
2(x²+16)=0
x²+16=0
x₁=√-16=4i
x₂=-4i

6x^2+11x-7=0
Δ=121+168=289
x₁=(-11+Δ289)/12
x₂=(-11-√289)/12